[Bug target/67391] [SH] Convert clrt addc to normal add insn

[kkojima at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67391

--- Comment #11 from Kazumoto Kojima <kkojima at gcc dot gnu.org> ---
(In reply to Oleg Endo from comment #10)
> The core issue should be fixed.  I'd like to keep this PR open though for a
> while.

I've got

/exp/ldroot/dodes/INTEST/trunk/gcc/testsuite/gfortran.dg/matmul_6.f90:19:0:
Error: could not split insn
(insn 2778 2779 94 (set (reg:SI 3 r3)
        (plus:SI (reg:SI 3 r3 [316])
            (const_int 372 [0x174])))
/exp/ldroot/dodes/INTEST/trunk/gcc/testsuite/gfortran.dg/matmul_6.f90:20 64
{*addsi3_compact}
     (nil))

in my local tree.  Clearly it was hidden by the wrong extra checks.