docs: cite the C64DTV ROM loaders in VICE

The three C64DTV ROM entries named only their file in vice/data. They now cite the BasicName, KernalName and ChargenName resources that name them, the c64rom loaders those resources call, and the embedded table that answers the names in the libretro build.

emulators/vice.yml

@@ -469,7 +469,7 @@ files:
     md5: 57af4ae21d4b705c2991d98ed5c1f7b8
     crc32: f833d117
     note: "C64 BASIC V2 ROM (DTV copy). Embedded in core."
-    source_ref: "vice/data/C64DTV/basic-901226-01.bin"
+    source_ref: "vice/data/C64DTV/basic-901226-01.bin, vice/src/c64/c64rom.h:31, vice/src/c64dtv/c64dtv-resources.c:92, 157, retrodep/embedded/c64dtvembedded.c:43-48"
 
   - name: "vice/C64DTV/chargen-901225-01.bin"
     system: commodore-c64dtv
@@ -481,7 +481,7 @@ files:
     md5: 12a4202f5331d45af846af6c58fba946
     crc32: ec4272ee
     note: "C64 Character Generator (DTV copy). Embedded in core."
-    source_ref: "vice/data/C64DTV/chargen-901225-01.bin"
+    source_ref: "vice/data/C64DTV/chargen-901225-01.bin, vice/src/c64/c64rom.h:60, vice/src/c64dtv/c64dtv-resources.c:74, 151, retrodep/embedded/c64dtvembedded.c:43-48"
 
   - name: "vice/C64DTV/kernal-901227-03.bin"
     system: commodore-c64dtv
@@ -493,7 +493,7 @@ files:
     md5: 39065497630802346bce17963f13c092
     crc32: dbe3e7c7
     note: "C64 Kernal Rev 3 (DTV copy). Embedded in core."
-    source_ref: "vice/data/C64DTV/kernal-901227-03.bin"
+    source_ref: "vice/data/C64DTV/kernal-901227-03.bin, vice/src/c64/c64rom.h:52, vice/src/c64dtv/c64dtv-resources.c:83, 154, retrodep/embedded/c64dtvembedded.c:43-48"
 
   # -------------------------------------------------------
   # VIC-20 ROMs (vice_xvic)