build: fixes a "can't cd to..." issue when installing shared libraries.

The problem is reproducible with a relative prefix path.

library.mak

@@ -72,7 +72,7 @@ install-lib$(NAME)-shared: $(SUBDIR)$(SLIBNAME)
 	$(Q)mkdir -p "$(SHLIBDIR)"
 	$$(INSTALL) -m 755 $$< "$(SHLIBDIR)/$(SLIB_INSTALL_NAME)"
 	$$(STRIP) "$(SHLIBDIR)/$(SLIB_INSTALL_NAME)"
-	$(Q)$(foreach F,$(SLIB_INSTALL_LINKS),cd "$(SHLIBDIR)" && $(LN_S) $(SLIB_INSTALL_NAME) $(F);)
+	$(Q)$(foreach F,$(SLIB_INSTALL_LINKS),(cd "$(SHLIBDIR)" && $(LN_S) $(SLIB_INSTALL_NAME) $(F));)
 	$(if $(SLIB_INSTALL_EXTRA_SHLIB),$$(INSTALL) -m 644 $(SLIB_INSTALL_EXTRA_SHLIB:%=$(SUBDIR)%) "$(SHLIBDIR)")
 	$(if $(SLIB_INSTALL_EXTRA_LIB),$(Q)mkdir -p "$(LIBDIR)")
 	$(if $(SLIB_INSTALL_EXTRA_LIB),$$(INSTALL) -m 644 $(SLIB_INSTALL_EXTRA_LIB:%=$(SUBDIR)%) "$(LIBDIR)")