[crew] minor fix (#2300)

delete all *.la files in single package, not only in DESTDIR/LIBDIR

crew

@@ -485,9 +485,9 @@ def prepare_package (destdir)
     # https://gnunet.org/faq-la-files
     # https://stackoverflow.com/questions/42963653/libquadmath-la-is-not-a-valid-libtool-archive-when-configuring-openmpi-with-g
     if @opt_verbose then
-      system "rm -rvf #{destdir}#{CREW_LIB_PREFIX}/*.la"
+      system "find #{destdir}#{CREW_LIB_PREFIX} -type f -name *.la -delete"
     else
-      system "rm -rf #{destdir}#{CREW_LIB_PREFIX}/*.la"
+      system "find #{destdir}#{CREW_LIB_PREFIX} -type f -name *.la -delete"
     end
 
     # create directory list