gsm_data.h: Drop duplicated include stdint.h

Change-Id: I7610cffc3a641975e05ba4ea9f469e12c99e407f
diff --git a/include/osmocom/bsc/gsm_data.h b/include/osmocom/bsc/gsm_data.h
index 0f5fc54..5336ebe 100644
--- a/include/osmocom/bsc/gsm_data.h
+++ b/include/osmocom/bsc/gsm_data.h
@@ -4,7 +4,6 @@
 #include <stdint.h>
 #include <sys/types.h>
 #include <stdbool.h>
-#include <stdint.h>
 
 #include <osmocom/core/timer.h>
 #include <osmocom/core/rate_ctr.h>