glsl: change ast_type_qualifier bitset size to work around GCC 5.4 bug

glsl: change ast_type_qualifier bitset size to work around GCC 5.4 bug

Change the size of the bitset from 128 bits to 96.  This works around an
apparent GCC 5.4 bug in which bad SSE code is generated, leading to a
crash in ast_type_qualifier::validate_in_qualifier() (ast_type.cpp:654).

This can be repro'd with the Piglit test tests/spec/glsl-1.50/execution/
varying-struct-basic-gs-fs.shader_test

Bugzilla:https://bugs.freedesktop.org/show_bug.cgi?id=105497
Cc: mesa-stable@lists.freedesktop.org
Reviewed-by: Charmaine Lee <charmainel@vmware.com>
Tested-by: Charmaine Lee <charmainel@vmware.com>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>