IB/ehca: Make symbols used only in a single source file static

Allow the compiler to optimize better and generate smaller code:

add/remove: 0/6 grow/shrink: 2/0 up/down: 1528/-1864 (-336)
function                                     old     new   delta
.ehca_set_pagebuf                           1344    2172    +828
.ehca_probe                                 2312    3012    +700
ehca_set_pagebuf_phys                         24       -     -24
ehca_set_pagebuf_fmr                          24       -     -24
ehca_init_device                              24       -     -24
.ehca_set_pagebuf_fmr                        480       -    -480
.ehca_set_pagebuf_phys                       512       -    -512
.ehca_init_device                            800       -    -800

Also this fixes warnings like:

    drivers/infiniband/hw/ehca/ehca_mrmw.c:2015:5: warning: symbol 'ehca_set_pagebuf_fmr' was not declared. Should it be static?

Signed-off-by: Roland Dreier <rolandd@cisco.com>
diff --git a/drivers/infiniband/hw/ehca/ehca_mrmw.c b/drivers/infiniband/hw/ehca/ehca_mrmw.c
index e239bbf..5e99c45 100644
--- a/drivers/infiniband/hw/ehca/ehca_mrmw.c
+++ b/drivers/infiniband/hw/ehca/ehca_mrmw.c
@@ -1952,9 +1952,8 @@
 	return ret;
 }
 
-int ehca_set_pagebuf_phys(struct ehca_mr_pginfo *pginfo,
-			  u32 number,
-			  u64 *kpage)
+static int ehca_set_pagebuf_phys(struct ehca_mr_pginfo *pginfo,
+				 u32 number, u64 *kpage)
 {
 	int ret = 0;
 	struct ib_phys_buf *pbuf;
@@ -2012,9 +2011,8 @@
 	return ret;
 }
 
-int ehca_set_pagebuf_fmr(struct ehca_mr_pginfo *pginfo,
-			 u32 number,
-			 u64 *kpage)
+static int ehca_set_pagebuf_fmr(struct ehca_mr_pginfo *pginfo,
+				u32 number, u64 *kpage)
 {
 	int ret = 0;
 	u64 *fmrlist;