tcg: Mark muluh_i64 and mulsh_i64 as 64-bit ops

Failure to do so results in the tcg optimizer sign-extending
any constant fold from 32-bits.  This turns out to be visible
in the RISC-V testsuite using a host that emits these opcodes
(e.g. any non-x86_64).
Reported-by: NMichael Clark <mjc@sifive.com>
Reviewed-by: NEmilio G. Cota <cota@braap.org>
Reviewed-by: NPhilippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>
(cherry picked from commit f2f1dde7)
Signed-off-by: NMichael Roth <mdroth@linux.vnet.ibm.com>

tcg/tcg-opc.h

@@ -182,8 +182,8 @@ DEF(add2_i64, 2, 4, 0, IMPL64 | IMPL(TCG_TARGET_HAS_add2_i64))
 DEF(sub2_i64, 2, 4, 0, IMPL64 | IMPL(TCG_TARGET_HAS_sub2_i64))
 DEF(mulu2_i64, 2, 2, 0, IMPL64 | IMPL(TCG_TARGET_HAS_mulu2_i64))
 DEF(muls2_i64, 2, 2, 0, IMPL64 | IMPL(TCG_TARGET_HAS_muls2_i64))
-DEF(muluh_i64, 1, 2, 0, IMPL(TCG_TARGET_HAS_muluh_i64))
-DEF(mulsh_i64, 1, 2, 0, IMPL(TCG_TARGET_HAS_mulsh_i64))
+DEF(muluh_i64, 1, 2, 0, IMPL64 | IMPL(TCG_TARGET_HAS_muluh_i64))
+DEF(mulsh_i64, 1, 2, 0, IMPL64 | IMPL(TCG_TARGET_HAS_mulsh_i64))
 
 #define TLADDR_ARGS  (TARGET_LONG_BITS <= TCG_TARGET_REG_BITS ? 1 : 2)
 #define DATA64_ARGS  (TCG_TARGET_REG_BITS == 64 ? 1 : 2)