eglibc: add version 2.19

Signed-off-by: Felix Fietkau <nbd@openwrt.org>

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@39742 3c298f89-4303-0410-b956-a3cf2f4a3e73
eglibc: remove versions 2.16 and 2.17 - they are unmaintained

Signed-off-by: Felix Fietkau <nbd@openwrt.org>

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@39743 3c298f89-4303-0410-b956-a3cf2f4a3e73
eglibc: use version 2.19 by default (lots of fixes, some security related)

Signed-off-by: Felix Fietkau <nbd@openwrt.org>

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@39744 3c298f89-4303-0410-b956-a3cf2f4a3e73