Fixing texture flags when forcing point sampling.

src/renderer_gl.cpp

@@ -4437,11 +4437,11 @@ namespace bgfx { namespace gl
 		&&  !s_textureFilter[m_textureFormat])
 		{
 			// Force point sampling when texture format doesn't support linear sampling.
-			_flags &= 0
+			_flags &= ~(0
 				| BGFX_TEXTURE_MIN_MASK
 				| BGFX_TEXTURE_MAG_MASK
 				| BGFX_TEXTURE_MIP_MASK
-				;
+				);
 			_flags |= 0
 				| BGFX_TEXTURE_MIN_POINT
 				| BGFX_TEXTURE_MAG_POINT