report supported function classes correctly on *-musl

gcc/
	* config/linux.c (linux_libc_has_function): Return true on musl.

From-SVN: r239860

gcc/ChangeLog

 2016-08-30  Szabolcs Nagy  <szabolcs.nagy@arm.com>
 
+	* config/linux.c (linux_libc_has_function): Return true on musl.
+
+2016-08-30  Szabolcs Nagy  <szabolcs.nagy@arm.com>
+
 	* config.gcc (*-*-*musl*): Disable gnu-indirect-function.
 
 2016-08-30  Eric Botcazou  <ebotcazou@adacore.com>

gcc/config/linux.c

@@ -26,7 +26,7 @@ along with GCC; see the file COPYING3.  If not see
 bool
 linux_libc_has_function (enum function_class fn_class)
 {
-  if (OPTION_GLIBC)
+  if (OPTION_GLIBC || OPTION_MUSL)
     return true;
   if (OPTION_BIONIC)
     if (fn_class == function_c94