makepkg: check for references to build root in package

Add a check that the package does not contain references to the
folder it was built in.

Fixes FS#14751

Signed-off-by: Allan McRae <allan@archlinux.org>
Signed-off-by: Dan McGee <dan@archlinux.org>

scripts/makepkg.sh.in

@@ -956,6 +956,11 @@ check_package() {
 			warning "$(gettext "Invalid backup entry : %s")" "$file"
 		fi
 	done
+
+	# check for references to the build directory
+	if grep -R "${srcdir}" "${pkgdir}" &>/dev/null; then
+		warning "$(gettext "Package contains reference to %s")" "\$srcdir"
+	fi
 }
 
 create_package() {