xtensa: avoid some compiler warnings

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Waldemar Brodkorb <wbx@uclibc-ng.org>

libpthread/nptl/sysdeps/unix/sysv/linux/xtensa/sysdep-cancel.h

@@ -25,6 +25,7 @@
 
 #if !defined NOT_IN_libc || defined IS_IN_libpthread || defined IS_IN_librt
 
+#ifdef __ASSEMBLER__
 #if defined(__XTENSA_WINDOWED_ABI__)
 /* CENABLE/CDISABLE in PSEUDO below use call8, stack frame size must be
  * at least 32.
@@ -117,6 +118,7 @@
 #else
 #error Unsupported Xtensa ABI
 #endif
+#endif
 
 # ifdef IS_IN_libpthread
 #  define CENABLE_FUNC	__pthread_enable_asynccancel