match.pd: Check trunc_mod vector obtap before folding.

match.pd: Check trunc_mod vector obtap before folding.

This patch guards the simplification x / y * y == x -> x % y == 0 in
match.pd by a check for:
1) Non-vector mode of x OR
2) Lack of support for vector division OR
3) Support of vector modulo

The patch was bootstrapped and tested with no regression on
aarch64-linux-gnu and x86_64-linux-gnu.
OK for mainline?

Signed-off-by: Jennifer Schmitz <jschmitz@nvidia.com>
gcc/
	PR tree-optimization/116831
	* match.pd: Guard simplification to trunc_mod with check for
	mod optab support.

gcc/testsuite/
	PR tree-optimization/116831
	* gcc.dg/torture/pr116831.c: New test.