nv30: report 8 maximum inputs
nv30: report 8 maximum inputs

nvfx_fragprog_assign_generic only allows for up to 10/8 texcoords for
nv40/nv30. This fixes compilation of the varying-packing tests.
Furthermore it appears that the last 2 inputs on nv4x don't seem to
work in those tests, so just report 8 everywhere for now.

Tested on NV42, NV44. NV4B appears to have additional problems.

Signed-off-by: Ilia Mirkin <bcbbb7aa705ec3a5fc5824c01a845186c3d62fca@alum.mit.edu>
Cc: 9.1 9.2 10.0 10.1 <59f39c0db42d4479a46b02d4d2bc11120e37bb44@lists.freedesktop.org>

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