rs6000/test: Adjust p9-vec-length-{full,epil}-7.c [PR103196]

rs6000/test: Adjust p9-vec-length-{full,epil}-7.c [PR103196]

As PR103196 shows, complete unrolling pass still takes effect even
if we have specified the option "-fno-unroll-loops".  The loops in
that case are not expected to be transformed by it, otherwise the
expected counts change.  This patch is to add the disabling option
to make them not sensitive to complete unrolling.

	PR testsuite/103196

gcc/testsuite/ChangeLog:

	* gcc.target/powerpc/p9-vec-length-epil-7.c: Add option
	-fdisable-tree-cunroll.
	* gcc.target/powerpc/p9-vec-length-full-7.c: Likewise.