configure: Add a SONAME entry for the android target

In order to load libraries in Android they need to be unversioned.
The android target section was derived from the BSD ones, and they
that simply drop the SONAME

Android M requires to have a SONAME entry but unversioned.

configure

@@ -3591,8 +3591,7 @@ case $target_os in
         enable section_data_rel_ro
         SLIB_INSTALL_NAME='$(SLIBNAME)'
         SLIB_INSTALL_LINKS=
-        # soname not set on purpose
-        SHFLAGS=-shared
+        SHFLAGS='-shared -Wl,-soname,$(SLIBNAME)'
         ;;
     haiku)
         prefix_default="/boot/common"