revision.h: turn rev_info.early_output back into an unsigned int

revision.h: turn rev_info.early_output back into an unsigned int

rev_info.early_output started out as an unsigned int in cdcefbc97 (Add
"--early-output" log flag for interactive GUI use, 2007-11-03), but
later it was turned into a single bit in a bit field in cc243c3ce
(show: --ignore-missing, 2011-05-18) without explanation, though the
code using it still expects it to be a regular integer type and uses
it as a counter.  Consequently, any even number given via
'--early-output=<N>', or indeed a plain '--early-output' defaulting to
100 effectively disabled the feature.

Turn rev_info.early_output back into its origin unsigned int data
type, making '--early-output' work again.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Reviewed-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>