arm: Add missing early clobber to MVE vrev64q_m patterns

arm: Add missing early clobber to MVE vrev64q_m patterns

Like the non-predicated vrev64q patterns, mve_vrev64q_m_<supf><mode>
and mve_vrev64q_m_f<mode> need an early clobber constraint, otherwise
we can generate an unpredictable instruction:

Warning: 64-bit element size and same destination and source operands makes instruction UNPREDICTABLE
when calling vrevq64_m* with the same first and second arguments.

OK for trunk?

Thanks,

Christophe

gcc/ChangeLog:

	* config/arm/mve.md (mve_vrev64q_m_<supf><mode>): Add early
	clobber.
	(mve_vrev64q_m_f<mode>): Likewise.

gcc/testsuite/ChangeLog:

	* gcc.target/arm/mve/intrinsics/vrev64q_m_s16-clobber.c: New test.