makepkg: do not run prepare() and pkgver() with --repackage

Bug introduced with commit 8454daa7.

Reported-by: Zuyi Hu <hzy068808@gmail.com>
Signed-off-by: Allan McRae <allan@archlinux.org>

scripts/makepkg.sh.in

@@ -2192,9 +2192,10 @@ mkdir -p "$srcdir"
 chmod a-s "$srcdir"
 cd_safe "$srcdir"
 
+if (( !REPKG )); then
 	if (( NOEXTRACT && ! VERIFYSOURCE )); then
 		warning "$(gettext "Using existing %s tree")" "\$srcdir/"
-elif (( !REPKG )); then
+	else
 		download_sources
 		check_source_integrity
 		(( VERIFYSOURCE )) && exit 0 # $E_OK
@@ -2215,6 +2216,7 @@ fi
 	if (( PREPAREFUNC )); then
 		run_prepare
 	fi
+fi
 
 if (( NOBUILD )); then
 	msg "$(gettext "Sources are ready.")"