rs6000, change altivec*-runnable.c test file names

Changed the names of the test files.

gcc/testsuite/ChangeLog:gcc/testsuite/ChangeLog:
	* gcc.target/powerpc/altivec-1-runnable.c: Change the name to
	altivec-38.c.
	* gcc.target/powerpc/altivec-2-runnable.c: Change the name to
	p8vector-builtin-9.c.

diff --git a/gcc/testsuite/gcc.target/powerpc/altivec-1-runnable.c b/gcc/testsuite/gcc.target/powerpc/altivec-38.c
similarity index 100%
rename from gcc/testsuite/gcc.target/powerpc/altivec-1-runnable.c
rename to gcc/testsuite/gcc.target/powerpc/altivec-38.c

diff --git a/gcc/testsuite/gcc.target/powerpc/altivec-2-runnable.c b/gcc/testsuite/gcc.target/powerpc/p8vector-builtin-9.c
similarity index 100%
rename from gcc/testsuite/gcc.target/powerpc/altivec-2-runnable.c
rename to gcc/testsuite/gcc.target/powerpc/p8vector-builtin-9.c