meta: Drop remnants of uclibc support

uclibc support was removed a while ago and musl works much better. Start to
remove the various overrides and patches related to uclibc which are no longer
needed.

uclibc support in a layer would still be possible. I have strong reasons to
believe nobody is still using uclibc since patches are missing and I doubt
the metadata even parses anymore.

(From OE-Core rev: 653704e9cf325cb494eb23facca19e9f05132ffd)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-devtools/elfutils/elfutils_0.168.bb

@@ -48,7 +48,6 @@ inherit autotools gettext
 
 EXTRA_OECONF = "--program-prefix=eu- --without-lzma"
 EXTRA_OECONF_append_class-native = " --without-bzlib"
-EXTRA_OECONF_append_libc-uclibc = " --enable-uclibc"
 
 do_install_append() {
 	if [ "${TARGET_ARCH}" != "x86_64" ] && [ -z `echo "${TARGET_ARCH}"|grep 'i.86'` ];then
@@ -56,11 +55,6 @@ do_install_append() {
 	fi
 }
 
-# we can not build complete elfutils when using uclibc
-# but some recipes e.g. gcc 4.5 depends on libelf so we
-# build only libelf for uclibc case
-
-EXTRA_OEMAKE_libc-uclibc = "-C libelf"
 EXTRA_OEMAKE_class-native = ""
 EXTRA_OEMAKE_class-nativesdk = ""