[Feature request] Autorepeat for P command

[ecm-pushbx]

I was surprised to find that the P command does not do autorepeat. I must have added that a long time ago in lDebug. G autorepeat is more complex. P is simple however.

[ecm-pushbx]

It's been in lDebug ever since I started keeping history in the SCM in 2010: https://hg.pushbx.org/ecm/ldebug/file/5eef5847c863/source/run.asm#l1026