install: do not strip libs when installing

We want unstripped binaries in staging; stripping is done by Buildroot
as a whole in target-finalize if needed, anyway.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>

diff --git a/libau/Makefile b/libau/Makefile
--- a/libau/Makefile
+++ b/libau/Makefile
@@ -37,7 +37,6 @@
 	ln -sf $< $@
 ${LibSo}.${LibSoMajor}: ${LibSo}.${LibSoMajor}.${LibSoMinor}
 	ln -sf $< $@
-${LibSo}.${LibSoMajor}.${LibSoMinor}: override LDFLAGS += -s
 ${LibSo}.${LibSoMajor}.${LibSoMinor}: override LDLIBS += -ldl -lpthread
 ${LibSo}.${LibSoMajor}.${LibSoMinor}: ${LibSoObj}
 	${CC} --shared -Wl,-soname,${LibSo}.${LibSoMajor} ${LDFLAGS} \