nouveau: always enable at least one RC
nouveau: always enable at least one RC

Experimentally, this is required for glxgears and others to display the
proper colors. This is also what the code used to do before the
referenced commit.

Fixes: c703658b396 (mesa: Drop _EnabledUnits.)
Signed-off-by: Ilia Mirkin <bcbbb7aa705ec3a5fc5824c01a845186c3d62fca@alum.mit.edu>
Cc: 59f39c0db42d4479a46b02d4d2bc11120e37bb44@lists.freedesktop.org

metora/MesaGLSLCompiler,metora/MesaGLSLCompiler,metora/MesaGLSLCompiler