[ui] progress bar improvements

* progress bar now reflects actual completion of process more closely
* dropped the use of UM_FORMAT_PROGRESS and introduced UpdateProgress() instead
* also reduced the number of rw test patterns from 4 to 2

src/badblocks.h

@@ -41,6 +41,7 @@ typedef struct ext2_struct_u32_iterate      *ext2_u32_iterate;
 #define EXT2_BAD_BLOCKS_THRESHOLD           256
 #define EXT2_BLOCKS_AT_ONCE                 64
 #define EXT2_SYS_PAGE_SIZE                  4096
+#define EXT2_RW_PATTERNS                    {0xaa, 0x55}
 
 enum test_types {
 	BADBLOCKS_RO,		/* Read-only */