Fix misreporting of omitted bytes for large remote packets

Fix misreporting of omitted bytes for large remote packets

In remote.c, when the output of "set debug remote" is truncated, the
number of characters reported is incorrect.  What is reported is the
number of characters added by the quoting, not the number of characters
that were truncated.

gdb/ChangeLog:

	* remote.c (putpkt_binary): Fix omitted bytes reporting.
	(getpkt_or_notif_sane_1): Likewise.