tools/mkimage: increase tmpfile name length limit

mkimage limits the length of the file paths in can deal with to 256
characters. Turns out that in automated builds by asu we break this
limit, so increase it to 1024 characters.

Signed-off-by: Daniel Golle <daniel@makrotopia.org>

tools/mkimage/patches/100-increase-tmpfile-name-length-limit.patch

@@ -0,0 +1,11 @@
+--- a/tools/mkimage.h
++++ b/tools/mkimage.h
+@@ -42,7 +42,7 @@ static inline ulong map_to_sysmem(void *
+ }
+ 
+ #define MKIMAGE_TMPFILE_SUFFIX		".tmp"
+-#define MKIMAGE_MAX_TMPFILE_LEN		256
++#define MKIMAGE_MAX_TMPFILE_LEN		1024
+ #define MKIMAGE_DEFAULT_DTC_OPTIONS	"-I dts -O dtb -p 500"
+ #define MKIMAGE_MAX_DTC_CMDLINE_LEN	2 * MKIMAGE_MAX_TMPFILE_LEN + 35
+