backport: re PR target/91150 (wrong code with -O -mavx512vbmi due to wrong writemask)

backport: re PR target/91150 (wrong code with -O -mavx512vbmi due to wrong writemask)

	Backported from mainline
	2019-07-30  Jakub Jelinek  <jakub@redhat.com>

	PR target/91150
	* config/i386/i386.c (expand_vec_perm_blend): Change mask type
	from unsigned to unsigned HOST_WIDE_INT.  For E_V64QImode cast
	comparison to unsigned HOST_WIDE_INT before shifting it left.

	* gcc.target/i386/avx512bw-pr91150.c: New test.

From-SVN: r275164