MIPS: Set condmove cost to SET(REG, REG)

MIPS: Set condmove cost to SET(REG, REG)

On most uarch, the cost condmove is same as other noraml integer,
and it should be COSTS_N_INSNS(1).

In GCC12 or previous, the condmove is always enabled, and from
GCC13, we start to compare the cost.

The generic rtx_cost give the result of COSTS_N_INSN(2).
Let's define it to COSTS_N_INSN(1) in mips_rtx_costs.

gcc
	* config/mips/mips.cc(mips_rtx_costs): Set condmove cost.
	* config/mips/mips.md(mov<GPR:mode>_on_<MOVECC:mode>,
	mov<GPR:mode>_on_<MOVECC:mode>_mips16e2,
	mov<GPR:mode>_on_<GPR2:mode>_ne
	mov<GPR:mode>_on_<GPR2:mode>_ne_mips16e2): Define name by
	remove starting *, so that we can use CODE_FOR_.

gcc/testsuite
	* gcc.target/mips/movcc-2.c: Add k?100:1000 test.