Add stdint include

Since st is using now int32_t and uint32_t the inclusion of
stdint or inttype is mandatory, because in other case the
definition of these new types will not be known by the
compiler.

st.c

@@ -11,6 +11,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <signal.h>
+#include <stdint.h>
 #include <sys/ioctl.h>
 #include <sys/select.h>
 #include <sys/stat.h>