Cleanup: use 'u' prefixed integer types for brevity & cast style

To use function style cast '(unsigned char)x' can't be replaced by
'unsigned char(x)'.

source/blender/sequencer/intern/disk_cache.c

@@ -69,7 +69,7 @@
 #define COLORSPACE_NAME_MAX 64 /* XXX: defined in IMB intern. */
 
 typedef struct DiskCacheHeaderEntry {
-  unsigned char encoding;
+  uchar encoding;
   uint64_t frameno;
   uint64_t size_compressed;
   uint64_t size_raw;