Give 64-bit comparison second operand a signed 33-bit immediate.
This is the smallest superset of uint32_t and int32_t, as used
by CLGFI and CGFI respectively. The rest of the 33-bit space
can be loaded into TCG_TMP0. Drop use of the constant pool.
Reviewed-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>