mesa: increase the relative address offset limit to 4096 in ARB_vp/fp

mesa: increase the relative address offset limit to 4096 in ARB_vp/fp

Even though the spec says that the limits should be -64/+63, proprietary
drivers support much larger relative offsets and some applications do
depend on this non-standard behavior.

Also program_parse.tab.c has been regenerated.

This fixes the parser error:

  ARB_vp: error: relative address offset too large

See also: https://bugs.freedesktop.org/show_bug.cgi?id=28628

4096 * sizeof(vec4) is the maximum size of the constant buffer on NV50.
It is not supposed to be a definite hardware limit, it is for the parser
not to get in the way and let the underlying driver decide whether it can
run the shader or not.