i965: Fix value of _3DPRIM_TRIFAN_NOSTIPPLE.
i965: Fix value of _3DPRIM_TRIFAN_NOSTIPPLE.

TRIFAN_NOSTIPPLE has always been 0x16 - 0x15 is marked "Reserved" on all
platforms.  See the 965 PRM, Volume 2, Table 3-1, "3D Primitive Topology
Type Encoding" for a list.

We don't currently use this, and I don't expect we will, but we may as
well not leave the bogus value around.

Signed-off-by: Kenneth Graunke <bd2562f754ec92342f93f61c25d731e290a2ffa8@whitecape.org>
Reviewed-by: Chris Forbes <5dcac483e7a6e31a5cbe89f38cc69dff8ee93dac@ijw.co.nz>

metora/MesaGLSLCompiler,metora/MesaGLSLCompiler,metora/MesaGLSLCompiler