Testsuite/MIPS: Fix msa.c: test7_v2f64, test7_v4f32, test43_v2i64

BNEGI.W/D are used for test7_v2f64 and test7_v4f32 now.  It is
an improvment since that we can save a instruction.

ILVR.D is used for test43_v2i64 now, instead of INSVE.D.

gcc/testsuite
	* gcc.target/mips/msa.c: Fix test7_v2f64, test7_v4f32 and
	test43_v2i64.