glibc: Fix up minimal build with libc-libm

This addresses 2 issues discovered trying to build a minimal libc with
libm option.  By default nscd was always being built and without inet
enabled there were missing symbols.

[YOCTO #7108]

(From OE-Core rev: 89649881bcd0e76d6ee7c85c30e75bb01e1c004f)

(From OE-Core rev: 965943176c580b7943bb4d94efd58b8818c04919)

Signed-off-by: Saul Wold <sgw@linux.intel.com>
Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Signed-off-by: Armin Kuster <akuster808@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-core/glibc/glibc/eglibc-use-option-groups.patch

@@ -4205,7 +4205,8 @@ Index: git/nss/getent.c
  D(gshadow)
 -D(hosts)
 +DN(hosts)
- D(initgroups)
+-D(initgroups)
++DN(initgroups)
 -D(netgroup)
 -D(networks)
 +DN(netgroup)

meta/recipes-core/glibc/glibc_2.20.bb

@@ -90,9 +90,12 @@ EXTRA_OECONF = "--enable-kernel=${OLDEST_KERNEL} \
                 --without-selinux \
                 --enable-obsolete-rpc \
                 --with-kconfig=${STAGING_BINDIR_NATIVE} \
+                --disable-nscd \
                 ${GLIBC_EXTRA_OECONF}"
 
 EXTRA_OECONF += "${@get_libc_fpu_setting(bb, d)}"
+EXTRA_OECONF += "${@bb.utils.contains('DISTRO_FEATURES', 'libc-inet-anl', '--enable-nscd', '--disable-nscd', d)}"
+
 
 do_patch_append() {
     bb.build.exec_func('do_fix_readlib_c', d)