vi: make context marks more like vi

The context marks that are automatically updated and can be used
with the "''" command didn't behave the same as in vi.  Marks
were only being set for certain editing commands when they should
have been set on successful movement commands.

Make BusyBox vi behave more like vi.

function                                             old     new   delta
.rodata                                           105179  105194     +15
do_cmd                                              4723    4668     -55
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(add/remove: 0/0 grow/shrink: 1/1 up/down: 15/-55)            Total: -40 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
1 file changed