tools: mkenvimage: Drop duplicate crc header include

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

Fixes: 3db71108575 ("crc32: Use the crc.h header for crc functions")
Signed-off-by: Marek Vasut <marex@denx.de>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/tools/mkenvimage.c b/tools/mkenvimage.c
index b05f834..a8eebab 100644
--- a/tools/mkenvimage.c
+++ b/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>