mjpg-streamer: remove outdated musl patch

It seems to not be needed anymore.

Signed-off-by: Rosen Penev <rosenp@gmail.com>

multimedia/mjpg-streamer/patches/005-musl_compatibility.patch

@@ -1,13 +0,0 @@
---- a/mjpg_streamer.h
-+++ b/mjpg_streamer.h
-@@ -29,6 +29,10 @@
- #define MAX_OUTPUT_PLUGINS 10
- #define MAX_PLUGIN_ARGUMENTS 32
- 
-+#define __NEED_pthread_t
-+#define __NEED_pthread_mutex_t
-+#define __NEED_pthread_cond_t
-+
- #include <linux/types.h>          /* for videodev2.h */
- #include <linux/videodev2.h>
- #include <pthread.h>