[SDL2] use %make_install for some reason

[Tom Callaway]

commit dd9ac298a308116adef59180c6c453a71a14f8c7
Author: Tom Callaway <spot at fedoraproject.org>
Date:   Thu Oct 24 12:01:15 2013 +0100

    use %make_install for some reason

 SDL2.spec |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/SDL2.spec b/SDL2.spec
index dbc5f68..f5a18dd 100644
--- a/SDL2.spec
+++ b/SDL2.spec
@@ -70,7 +70,7 @@ sed -i -e 's/\r//g' TODO.txt README.txt WhatsNew.txt BUGS.txt COPYING.txt CREDIT
 make %{?_smp_mflags}
 
 %install
-make DESTDIR=%{buildroot} install
+%make_install
 
 # Rename SDL_config.h to SDL_config-<arch>.h to avoid file conflicts on
 # multilib systems and install SDL_config.h wrapper