busybox

flash_eraseall: stop using obsolete mtd/jffs2-user.h; code shrink

function                                             old     new   delta
show_progress                                         68      67      -1
flash_eraseall_main                                 1007     882    -125
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(add/remove: 0/0 grow/shrink: 0/2 up/down: 0/-126)           Total: -126 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>