Implement glTexParameterx().
Implement glTexParameterx().

All current texture parameters are integer, so just pass them through to
glTexParameteri().

Change-Id: Ic4042b26b31194916af7814cabf2eb0d22c76ecb
Reviewed-on: https://swiftshader-review.googlesource.com/2710
Tested-by: Greg Hartman <1491e78df1ea2169b62fa2ceaf1a32538792aab8@google.com>
Reviewed-by: Greg Hartman <1491e78df1ea2169b62fa2ceaf1a32538792aab8@google.com>
Reviewed-by: Nicolas Capens <0612353e1fcebbfd4b302d9337447ca0cdfa9122@google.com>

google/swiftshader,bkaradzic/SwiftShader,bkaradzic/SwiftShader,bkaradzic/SwiftShader,bkaradzic/SwiftShader,google/swiftshader,google/swiftshader,bkaradzic/SwiftShader