re PR target/51244 ([SH] Inefficient conditional branch and code around T bit)

	PR target/51244
	* config/sh/sh.c (prepare_cbranch_operands): Pull out comparison
	canonicalization code into...
	* (sh_canonicalize_comparison): This new function.
	* config/sh/sh-protos.h: Declare it.
	* config/sh/sh.h: Use it in new macro CANONICALIZE_COMPARISON.
	* config/sh/sh.md (cbranchsi4): Remove TARGET_CBRANCHDI4 check and
	always invoke expand_cbranchsi4.

From-SVN: r190909