imlib2: fix imlib2-config

[Peter: use a single sed invocation]
Signed-off-by: Stefan Fröberg <stefan.froberg@petroprogram.com>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>

package/imlib2/imlib2.mk

@@ -57,7 +57,9 @@ endif
 
 # drop -L<dir> from linker flags
 define IMLIB2_FIXUP_IMLIB2_CONFIG
-	$(SED) 's/-L[^ ]*//g' \
+	$(SED) "s,^prefix=.*,prefix=\'$(STAGING_DIR)/usr\',g" \
+		-e "s,^exec_prefix=.*,exec_prefix=\'$(STAGING_DIR)/usr\',g" \
+		-e  's/-L[^ ]*//g' \
 		$(STAGING_DIR)/usr/bin/imlib2-config
 endef