[PATCH] RISC-V: Move UNSPEC_SSP_SET and UNSPEC_SSP_TEST to correct enum

stack_protect_{set,test}_<mode> were showing up in RTL dumps as
UNSPEC_COPYSIGN and UNSPEC_FMV_X_W due to UNSPEC_SSP_SET and
UNSPEC_SSP_TEST being put in the unspecv enum instead of unspec.

gcc/ChangeLog:

	* config/riscv/riscv.md: Move UNSPEC_SSP_SET and UNSPEC_SSP_TEST
	to unspec enum.