Fix libdir field of libtool files (*.la) generated in router stage dir

[Vigilans]

The stage dir (release/src/router/arm-glibc/stage/usr/lib) contains some libtool files (*.la) with a wrong libdir (normally /usr/lib), and compilation will break when referencing such wrong libtool files, while users have their corresponding libs installed in build machine's architecture.

Previous commits have made some fix to this problem by substituting wrong libdir with the correct one ($(STAGEDIR)/usr/lib) by sed. This pull request tries to apply such fix to all possible libtool files generated in frimware compilation (collected in building rt-ax86u):

release/src/router/arm-glibc/stage/usr/lib/libcharset.la
release/src/router/arm-glibc/stage/usr/lib/libconfuse.la
release/src/router/arm-glibc/stage/usr/lib/libcurl.la
release/src/router/arm-glibc/stage/usr/lib/libdaemon.la
release/src/router/arm-glibc/stage/usr/lib/libevent.la
release/src/router/arm-glibc/stage/usr/lib/libevent_core.la
release/src/router/arm-glibc/stage/usr/lib/libevent_extra.la
release/src/router/arm-glibc/stage/usr/lib/libevent_pthreads.la
release/src/router/arm-glibc/stage/usr/lib/libexpat.la
release/src/router/arm-glibc/stage/usr/lib/libiconv.la
release/src/router/arm-glibc/stage/usr/lib/libipset.la
release/src/router/arm-glibc/stage/usr/lib/libjansson.la
release/src/router/arm-glibc/stage/usr/lib/libjson-c.la
release/src/router/arm-glibc/stage/usr/lib/liblzo2.la
release/src/router/arm-glibc/stage/usr/lib/libmnl.la
release/src/router/arm-glibc/stage/usr/lib/libneon.la
release/src/router/arm-glibc/stage/usr/lib/libxml2.la
release/src/router/arm-glibc/stage/usr/lib/libyaml.la

So compilation will not break when users have installed libraries like libxml2 in their build machine's architecture.