GKI cleanup - Replaced usage of GKI queue with OSI fixed_queue

* Added new functions to OSI:
  - fixed_queue_init()
  - fixed_queue_length()
  - fixed_queue_try_remove_from_queue()
  - fixed_queue_try_peek_last()

* Renamed fixed_queue_try_peek() to fixed_queue_try_peek_first()

* Replaced usage of GKI queue functions with OSI fixed_queue functions:
  - GKI_init_q() -> fixed_queue_new(SIZE_MAX)
    NOTE: unlike GKI_init_q(), fixed_queue_new() allocates memory /
    state that needs to be released by calling fixed_queue_free()
  - GKI_enqueue() -> fixed_queue_enqueue()
  - GKI_dequeue() -> fixed_queue_try_dequeue()
    NOTE: fixed_queue_try_dequeue() is non-blocking
  - GKI_queue_length() -> fixed_queue_length()
  - GKI_queue_is_empty() -> fixed_queue_is_empty()
  - GKI_getfirst() -> fixed_queue_try_peek_first()
  - GKI_getlast() -> fixed_queue_try_peek_last()
  - GKI_remove_from_queue() -> fixed_queue_try_remove_from_queue()
  - Queue elements iteration.
    In the fixed_queue implementation we have to use the underlying
    list_t mechanism to iterate over the elements.
    OLD:
      p = GKI_getfirst(queue);
      ...
      while ((p = GKI_getnext(p) != NULL) {
         ...
      }
    NEW:
      list_t *list = fixed_queue_get_list(queue);
      for (const list_node_t *node = list_begin(list);
           node != list_end(list); node = list_next(node)) {
          p = list_node(node);
      }

* Remove initialization of the GKI module, because it is not needed
  anymore

* Removed unused files in GKI:
  gki/common/gki_common.h
  gki/ulinux/gki_int.h
  gki/ulinux/gki_ulinux.c

Change-Id: I3ff9464db75252d6faf7476a9ca67c88e535c51c
diff --git a/stack/avdt/avdt_int.h b/stack/avdt/avdt_int.h
index fb1b313..b696dd8 100644
--- a/stack/avdt/avdt_int.h
+++ b/stack/avdt/avdt_int.h
@@ -24,6 +24,7 @@
 #ifndef AVDT_INT_H
 #define AVDT_INT_H
 
+#include "osi/include/fixed_queue.h"
 #include "gki.h"
 #include "avdt_api.h"
 #include "avdtc_api.h"
@@ -423,8 +424,8 @@
 typedef struct {
     BD_ADDR             peer_addr;      /* BD address of peer */
     TIMER_LIST_ENT      timer_entry;    /* CCB timer list entry */
-    BUFFER_Q            cmd_q;          /* Queue for outgoing command messages */
-    BUFFER_Q            rsp_q;          /* Queue for outgoing response and reject messages */
+    fixed_queue_t       *cmd_q;         /* Queue for outgoing command messages */
+    fixed_queue_t       *rsp_q;         /* Queue for outgoing response and reject messages */
     tAVDT_CTRL_CBACK    *proc_cback;    /* Procedure callback function */
     tAVDT_CTRL_CBACK    *p_conn_cback;  /* Connection/disconnection callback function */
     void                *p_proc_data;   /* Pointer to data storage for procedure */
@@ -450,7 +451,7 @@
     BT_HDR      *p_buf;
     UINT32      time_stamp;
 #if AVDT_MULTIPLEXING == TRUE
-    BUFFER_Q    frag_q;          /* Queue for outgoing media fragments. p_buf should be 0 */
+    fixed_queue_t *frag_q;              /* Queue for outgoing media fragments. p_buf should be 0 */
     UINT8       *p_data;
     UINT32      data_len;
 #endif
@@ -496,7 +497,7 @@
     BOOLEAN         cong;           /* Whether media transport channel is congested */
     UINT8           close_code;     /* Error code received in close response */
 #if AVDT_MULTIPLEXING == TRUE
-    BUFFER_Q        frag_q;         /* Queue for outgoing media fragments */
+    fixed_queue_t   *frag_q;        /* Queue for outgoing media fragments */
     UINT32          frag_off;       /* length of already received media fragments */
     UINT32          frag_org_len;   /* original length before fragmentation of receiving media packet */
     UINT8           *p_next_frag;   /* next fragment to send */
@@ -669,7 +670,8 @@
 extern void avdt_scb_clr_pkt(tAVDT_SCB *p_scb, tAVDT_SCB_EVT *p_data);
 extern void avdt_scb_tc_timer(tAVDT_SCB *p_scb, tAVDT_SCB_EVT *p_data);
 extern void avdt_scb_clr_vars(tAVDT_SCB *p_scb, tAVDT_SCB_EVT *p_data);
-extern void avdt_scb_queue_frags(tAVDT_SCB *p_scb, UINT8 **pp_data, UINT32 *p_data_len, BUFFER_Q *pq);
+extern void avdt_scb_queue_frags(tAVDT_SCB *p_scb, UINT8 **pp_data,
+                                 UINT32 *p_data_len, fixed_queue_t *pq);
 
 /* msg function declarations */
 extern BOOLEAN avdt_msg_send(tAVDT_CCB *p_ccb, BT_HDR *p_msg);