tools: mkenvimage: Drop duplicate crc header include

This header was already included just above version.h,
do not include it twice.

Fixes: 3db7110857 ("crc32: Use the crc.h header for crc functions")
Signed-off-by: Marek Vasut <marex@denx.de>
Reviewed-by: Simon Glass <sjg@chromium.org>

tools/mkenvimage.c

@@ -14,7 +14,6 @@
 #include <stdlib.h>
 #include <stdint.h>
 #include <string.h>
-#include <u-boot/crc.h>
 #include <unistd.h>
 #include <libgen.h>
 #include <sys/types.h>