docs: Add GL_EXT_shader_samples_identical to the release notes
docs: Add GL_EXT_shader_samples_identical to the release notes

Trivial

Signed-off-by: Ian Romanick <2b237cafb16dc45038e85df6c85e74e6d899eba9@intel.com>

metora/MesaGLSLCompiler,metora/MesaGLSLCompiler,metora/MesaGLSLCompiler