[Mips] Fix clang crashes when assembling invalid MIPS beql instructions with --arch=mips (#156413)

From clang version 4, mips append new instruction BeqImm and
BEQLImm, the second operand format of instruction is imm64:$imm.

1.When Mips process `beql $t0, ($t0), 1`, it think the second operand
was an imm, so match success. Then mips backend process expandBranchImm,
check the second operand `$t0` was not imm, reported asserts.
We can strengthen the second operand matching restrictions.

2.Similarly, when Mips process `beql $t0, (1), 1`, it think the second
was an imm. so match success. Then mips backend process expandBranchImm,
check the third operand `1` was not expression, reported asserts. Permit
the third operand of `beql`  to be imm.

Fixes #151453.

0 files changed, 0 insertions, 0 deletions