refactor: fold vba_m into the vbam profile

vba_m carried md5 values taken from docs.libretro.com while its entries
declare validation: [size], which is what src/gba/GBA.cpp:3262-3272 and
src/gb/GB.cpp:2172-2192 actually check. Only the source decides a hash,
so they are gone.

The profile becomes an alias of vbam, and the buildbot name vba-m moves
into its cores: list so target filtering still resolves it.

emulators/vba_m.yml

@@ -1,32 +1,5 @@
-# VBA-M — Game Boy / Game Boy Color / Game Boy Advance (libretro)
-# ref: visualboyadvance-m/src/libretro, docs.libretro.com/library/vba_m
-# Same BIOS as mGBA. Requires core option "Use BIOS file if found" = On.
-#
-# doc vs source: docs list gba_bios.bin md5 a860e8c0b6d573d191e4ec7db1b1e4f6
-# which is the standard GBA BIOS dump. Also accepts gb_bios.bin and gbc_bios.bin
-# for GB/GBC mode (not listed in mgba profile).
 emulator: VBA-M
-type: libretro
-cores: [vbam, vba-m]
-source: "https://github.com/visualboyadvance-m/visualboyadvance-m"
-systems:
-  - nintendo-gb
-  - nintendo-gbc
-  - nintendo-gba
-files:
-  - name: gba_bios.bin
-    system: nintendo-gba
-    required: false
-    hle_fallback: true
-    md5: a860e8c0b6d573d191e4ec7db1b1e4f6
-    note: "optional, core option vbam_usebios must be On"
-  - name: gb_bios.bin
-    system: nintendo-gb
-    required: false
-    hle_fallback: true
-    md5: 32fbbd84168d3482956eb3c5051637f5
-  - name: gbc_bios.bin
-    system: nintendo-gbc
-    required: false
-    hle_fallback: true
-    md5: dbfce9db9deaa2567f6a84fde55f9680
+type: alias
+alias_of: vbam
+note: Legacy profile key retained for platform and buildbot compatibility.
+files: []

emulators/vbam.yml

@@ -9,6 +9,7 @@ core_version: "2.1.4"
 display_name: "Nintendo - Game Boy Advance (VBA-M)"
 cores:
   - vbam
+  - vba-m
 systems:
   - nintendo-gba
   - nintendo-gb