hvc_console: Provide (un)locked version for hvc_resize()

Rename the locking free hvc_resize() function to __hvc_resize() and
provide an inline function that locks the hvc_struct and calls
__hvc_resize().

The rationale for this patch is that virtio_console calls the hvc_resize()
function without locking the hvc_struct. So it needs to call the lock
itself.

According to naming rules, the unlocked version is renamed and
prefixed with "__".
References to unlocked function calls in hvc back-ends has been updated.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/drivers/char/hvc_console.c b/drivers/char/hvc_console.c
index 25ce15b..a632f25 100644
--- a/drivers/char/hvc_console.c
+++ b/drivers/char/hvc_console.c
@@ -678,7 +678,7 @@
 EXPORT_SYMBOL_GPL(hvc_poll);
 
 /**
- * hvc_resize() - Update terminal window size information.
+ * __hvc_resize() - Update terminal window size information.
  * @hp:		HVC console pointer
  * @ws:		Terminal window size structure
  *
@@ -687,12 +687,12 @@
  *
  * Locking:	Locking free; the function MUST be called holding hp->lock
  */
-void hvc_resize(struct hvc_struct *hp, struct winsize ws)
+void __hvc_resize(struct hvc_struct *hp, struct winsize ws)
 {
 	hp->ws = ws;
 	schedule_work(&hp->tty_resize);
 }
-EXPORT_SYMBOL_GPL(hvc_resize);
+EXPORT_SYMBOL_GPL(__hvc_resize);
 
 /*
  * This kthread is either polling or interrupt driven.  This is determined by