imsettings: Disable two warnings with clang

clang is fussy and this package is old. It should perhaps
be removed but this keeps it going so let it be.

Signed-off-by: Khem Raj <raj.khem@gmail.com>

meta-xfce/recipes-extended/imsettings/imsettings_1.8.10.bb

@@ -31,6 +31,7 @@ EXTRA_OECONF = "--with-xinputsh=50-xinput.sh \
                 --disable-static \
                "
 
+CFLAGS:append:toolchain-clang = " -Wno-error=unused-function -Wno-error=single-bit-bitfield-constant-conversion"
 PACKAGECONFIG ??= "xfce"
 PACKAGECONFIG[xfce] = ",,xfconf"
 PACKAGECONFIG[xim] = ",,libgxim"