Fix accidental ABI usage in RANDR 1.2 drivers.

Due to RANDR 1.2, xf86findOptionValue and xf86nameCompare are now ABI.
Make sure they're exported from the server.

hw/xfree86/parser/Flags.c

@@ -330,7 +330,7 @@ xf86findOption (XF86OptionPtr list, const char *name)
  * returned.  If the option is not found, a NULL is returned.
  */
 
-char *
+__attribute__((visibility("default"))) char *
 xf86findOptionValue (XF86OptionPtr list, const char *name)
 {
 	XF86OptionPtr p = xf86findOption (list, name);

hw/xfree86/parser/scan.c

@@ -948,7 +948,7 @@ StringToToken (char *str, xf86ConfigSymTabRec * tab)
  * Compare two names.  The characters '_', ' ', and '\t' are ignored
  * in the comparison.
  */
-int
+__attribute__((visibility("default"))) int
 xf86nameCompare (const char *s1, const char *s2)
 {
 	char c1, c2;