mesa: Don't check for API_OPENGLES in _mesa_uniform_matrix

mesa: Don't check for API_OPENGLES in _mesa_uniform_matrix

There are no uniforms in OpenGL ES 1.x, so we can't even get to this
code in that API.

Also, reorder the checks.  First check that transpose is true, then
check whether or not that is legal in the current API.  transpose should
never be true in an ES2 context, so this gets one check (the more
expensive one) out of the main path.

Valgrind callgrind results for a trace of Tesseract:

                 _mesa_UniformMatrix4fv  _mesa_UniformMatrix3fv
Before (64-bit):             96,119,025              24,240,510
After  (64-bit):             90,726,569              22,926,662

                 _mesa_UniformMatrix4fv  _mesa_UniformMatrix3fv
Before (32-bit):            132,434,452              29,051,808
After  (32-bit):            126,658,112              27,989,316

Signed-off-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Tapani Pälli <tapani.palli@intel.com>