testsuite, rs6000: Adjust pcrel-sibcall-1.c with noipa [PR112751]

As PR112751 shows, commit r14-5628 caused pcrel-sibcall-1.c
to fail as it enables ipa-vrp which makes return values of
functions {x,y,xx} as known and propagated.  This patch is
to adjust it with noipa to make it not fragile.

	PR testsuite/112751

gcc/testsuite/ChangeLog:

	* gcc.target/powerpc/pcrel-sibcall-1.c: Replace noinline as noipa.

Author: jedilyn

gcc/testsuite/gcc.target/powerpc/pcrel-sibcall-1.c

@@ -8,10 +8,10 @@
    generated when the caller preserves the TOC but the callee does not.  */
 
 #pragma GCC target ("cpu=power10,pcrel")
-int x (void) __attribute__((noinline));
-int y (void) __attribute__((noinline));
-int xx (void) __attribute__((noinline));
-  
+int x (void) __attribute__((noipa));
+int y (void) __attribute__((noipa));
+int xx (void) __attribute__((noipa));
+
 int x (void)
 {
   return 1;