[22/77] Replace !VECTOR_MODE_P with is_a <scalar_int_mode>

[22/77] Replace !VECTOR_MODE_P with is_a <scalar_int_mode>

This patch replaces some checks of !VECTOR_MODE_P with checks
of is_a <scalar_int_mode>, in cases where the scalar integer
modes were the only useful alternatives left.

2017-08-30  Richard Sandiford  <richard.sandiford@linaro.org>
	    Alan Hayward  <alan.hayward@arm.com>
	    David Sherwood  <david.sherwood@arm.com>

gcc/
	* simplify-rtx.c (simplify_binary_operation_1): Use
	is_a <scalar_int_mode> instead of !VECTOR_MODE_P.

Co-Authored-By: Alan Hayward <alan.hayward@arm.com>
Co-Authored-By: David Sherwood <david.sherwood@arm.com>
From-SVN: r251474