intel: Don't try to blorp or blit CopyTexSubImage(1D_ARRAY).

Blorp and the hardware blitter can't be used to implement
CopyTexSubImage when the image type is 1D_ARRAY, because of a
coordinate system mismatch (the Y coordinate in the source image is
supposed to be matched up to the Z coordinate in the destination
texture).

The hardware blitter path (intel_copy_texsubimage) contained a perf
debug warning for this case, but it failed to actually fall back.  The
blorp path didn't even check.

Fixes piglit test "copyteximage 1D_ARRAY".