edevices/edevices.cpp: Added additional video priority modes used by Mortal Race.
New working systems
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Mortal Race [Museo del Recreativo, David Haywood, ClawGrip]
Side note: this changes the semantics of read_pc to what was formerly known as read_pc_noinc. Now that memory accesses themselves can be interrupted and restarted, updating PC as a side effect is obsolete anyway.
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Player's Edge Plus (X000014P+XP000055) Standard Draw Poker [Brian Troha]
Player's Edge Plus (X002002P+XP000038) Double Double Bonus Poker [Brian Troha]
Player's Edge Plus (X002046P+XP000038) Ace$ Bonus Poker [Brian Troha]
New working clones
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Player's Edge Plus (BE0013) Blackjack [Brian Troha]
Player's Edge Plus (PP0005) Standard Draw Poker [Brian Troha]
Player's Edge Plus (PP0042) 10's or Better (set 1) [Brian Troha]
Player's Edge Plus (PP0083) 10's or Better (set 1) [Brian Troha]
Player's Edge Plus (PP0094) Standard Draw Poker (set 2) [Brian Troha]
Player's Edge Plus (PP0117) Standard Draw Poker [Brian Troha]
Player's Edge Plus (PP0122) Deuces Wild Poker [Brian Troha]
Player's Edge Plus (PP0143) Deuces Joker Wild Poker [Brian Troha]
Player's Edge Plus (PP0418) Deuces Wild Poker (set 1) [Brian Troha]
Player's Edge Plus (PP0420) Standard Draw Poker (set 1) [Brian Troha]
Player's Edge Plus (PP0425) Joker Poker [Brian Troha]
Player's Edge Plus (PP0430) Deuces Joker Wild Poker (set 1) [Brian Troha]
Player's Edge Plus (PP0451) Bonus Poker Deluxe [Brian Troha]
Player's Edge Plus (PP0459) Joker Poker (set 1) [Brian Troha]
Player's Edge Plus (PP0469) Deuces Wild Poker [Brian Troha]
Player's Edge Plus (PP0508) Loose Deuce Deuces Wild! Poker (set 1) [Brian Troha]
Player's Edge Plus (PP0540) Double Bonus Poker (set 1) [Brian Troha]
Player's Edge Plus (PP0729) Double Bonus Poker [Brian Troha]
Player's Edge Plus (PP0750) Standard Draw Poker (set 1) [Brian Troha]
Player's Edge Plus (PP0777) Royal Deuces Poker?? [Brian Troha]
New clones marked not working
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Montana Choice (MG0225) Multi-Game [Brian Troha]
Player's Edge (PK0785-PC041) Tens or Better [Brian Troha]
Player's Edge (PK0788-PC041) Tens or Better [Brian Troha]
Player's Edge (PK1015-PC088) 4 of a Kind Bonus Poker [Brian Troha]
Player's Edge (PK1031-PC088) 4 of a Kind Bonus Poker [Brian Troha]
Player's Edge Plus (KE0026) Keno [Brian Troha]
Player's Edge Plus (PP0079) Standard Draw Poker [Brian Troha]
Read callbacks now need a default return value supplied at construction.
Replaced isnull() with isunset() which tells you if the callback wasn't
configured rather than whether it isn't safe to call.
Enabled validation of device callbacks (it seems it was disabled at some
point, probably accidentally).
Device callbacks and object finders now implement the same interface for
resolution.
This reverts commit 2c0246059f.
This PR obviously wasn't reviewed properly. It has very obvious issues,
in particular:
* Resetting child devices from device_reset/machine_reset. Child
devices are automatically reset when a device is reset.
* Changing input state on reset. This leads to state getting out of
sync. Devices that change their outputs on reset are responsible for
pushing out the update.
New systems marked not working
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Roland Music Style Card TN-SC2 Software List holder
New software list items marked not working
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r8_card: SN-R8-09 Power Drums U.S.A.
roland_tnsc2: TN-SC2-04 Dance
u110_card: SN-SPLA-01 Sound Elements Vol. 1 (U-01)
