[AArch64] Simplify SVE IFN_COND patterns

[AArch64] Simplify SVE IFN_COND patterns

This patch makes the binary IFN_COND patterns use the same approach
as the ternary patterns, with one pattern handling the cases in
which the "else" value isn't tied to one of the other inputs.

2019-06-18  Richard Sandiford  <richard.sandiford@arm.com>
	    Kugan Vivekanandarajah  <kuganv@linaro.org>

gcc/
	* config/aarch64/aarch64-sve.md (*cond_<optab><mode>_0): Delete.
	(*cond_<optab><mode>_z): Fold into...
	(*cond_<optab><mode>_any): ...here.  Also handle cases in which
	operand 4 can be tied to operand 0 (either inherently or via RA).

From-SVN: r272423