mesa: remove header provided by other package

In case of Gcnano-userland-binary are used,
the KHR include are provided by this package and
there is a conflict with mesa-gl.


Signed-off-by: Christophe Priouzeau <christophe.priouzeau@st.com>

recipes-graphics/mesa/mesa-gl_%.bbappend

@@ -0,0 +1,3 @@
+do_install_append_stm32mpcommon() {
+    rm -rf ${D}/usr/include/KHR
+}