i965: Don't write beyond allocated memory.
i965: Don't write beyond allocated memory.

Reviewed-by: Eduardo Lima Mitev <86e6f0c9eba14994f25948ad50c226b324e9fa92@igalia.com>
Reviewed-by: Matt Turner <789b315743a28dd066a4ba1459c35951c291d8a6@gmail.com>
Signed-off-by: Juha-Pekka Heikkila <cab67866509becb852d2a4e6f7e5924ad04fb975@gmail.com>

metora/MesaGLSLCompiler,metora/MesaGLSLCompiler,metora/MesaGLSLCompiler