Minor enhancement - SMSAdvance implementation

[OmDRetro]

Bug for tracking purposes

Checked the header format from the last known version (SMSAdvance v2.5)

Header data consists of the ff.:

Size	Header Info
4 bytes	Identifier = "SMS",0x1A
4 bytes	ROM size
2 bytes	ROM flags
1 byte	Branch hacks, bit 0-3: opcode, bit 4-7: length. (not yet).
1 byte	Reserved (set to 0)
4 bytes	Autoscroll value (a.k.a. "sprite following")
1 byte	BIOS flag, bit0=1 for BIOS rom.
15 bytes	Reserved (set to 0)
32 bytes	ROM title (NULL terminated)

---

ROM flags:

• Bit 0: Use PAL timing
  • (0=NTSC, 1=PAL)
• Bit 1: Domestic bit
  • (0=Usa/Europe, 1=Japan)
• Bit 2: GameGear
  • (0=SMS, 1=GG)
• Bit 3: SMS2
  • (0=SMS, 1=SMS2)
• Bit 4: Enable CPU speed hack
  • (Enables the branch hacks)
• Bit 5: 0=Autoscroll value is a sprite number
  • 1=Autoscroll value is a memory location
• Everything else: Reserved (set to 0)

[OmDRetro]

Seems the identifier is terminated with a hex value. Based on what the compilation executable does, also called SMSAdvance, the output rom has 0x1A (shifted left by 24 bits)

[OmDRetro]

Done! Pushed changes via commit 3adbe6f