dot-a.eclass: exit early if static-libs use disabled

Otherwise it will try to run inside the build directory if there is a
static-libs use flag which is disabled.

llvm-bitcode-strip: error: './build/obj/lib/x509_x509path.o': The file was not recognized as a valid object file

Signed-off-by: Alfred Wingate <parona@protonmail.com>
Signed-off-by: Sam James <sam@gentoo.org>

eclass/dot-a.eclass

@@ -84,6 +84,8 @@ strip-lto-bytecode() {
 			# so we expect to be called on *something*, but nothing was explicitly
 			# passed. Try scanning ${ED} automatically.
 			set -- "${ED}"
+		else
+			return
 		fi
 	fi