mesa: Fix copy-and-paste bug in do_row_3D

Several of the half-float cases used 4 as the texel size when it
should have been some smaller value.

NOTE: This is a candidate for the 8.0 branch.

Signed-off-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=43324
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=43325
1 file changed