multilib_header: Do not install mutlilib headers for musl

musl is not multilib and this creates trouble. eg. when
util-linux probes for ncurses it does not find it because
ncurses has installed the multilibbed header and this
header includes bits/wordsize.h and this header does not
exist on musl systems. If and when musl adds multilib
support we will revisit it.

(From OE-Core rev: dad1c2746326912db41a3ff180679cdfe0e844f9)

Signed-off-by: Khem Raj <raj.khem@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/classes/multilib_header.bbclass

@@ -6,6 +6,13 @@ inherit siteinfo
 # all of the ABI variants for that given architecture.
 #
 oe_multilib_header() {
+
+	case ${HOST_OS} in
+	*-musl*)
+		return
+		;;
+	*)
+	esac
         # We use
         # For ARM: We don't support multilib builds.
         # For MIPS: "n32" is a special case, which needs to be