Point submodules to Libretro repositories

.gitmodules

@@ -3,7 +3,7 @@
 	url = https://github.com/libretro/libretro-common.git
 [submodule "libretro/retro_frontend"]
 	path = retro_frontend
-	url = git://depot.h4ck.me/srv/git/retro_frontend
+	url = https://git.sr.ht/~ehmry/retro_frontend
 [submodule "libretro/cores/2048/core"]
 	path = cores/2048/upstream
 	url = https://github.com/libretro/libretro-2048
@@ -18,10 +18,10 @@
 	url = https://github.com/libretro/mgba.git
 [submodule "libretro/cores/nxengine/core"]
 	path = cores/nxengine/upstream
-	url = git://depot.h4ck.me/srv/git/nxengine
+	url = https://github.com/libretro/nxengine-libretro.git
 [submodule "libretro/cores/oberon/core"]
 	path = cores/oberon/upstream
-	url = git@github.com:ehmry/oberon-risc-libretro.git
+	url = https://github.com/pdewacht/oberon-risc-libretro.git
 [submodule "libretro/cores/snes9x/core"]
 	path = cores/snes9x/upstream
 	url = https://github.com/libretro/snes9x.git
@@ -36,10 +36,10 @@
 	url = https://github.com/libretro/dosbox-libretro
 [submodule "libretro/cores/mrboom/core"]
 	path = cores/mrboom/upstream
-	url = git@github.com:ehmry/mrboom-libretro.git
+	url = https://github.com/libretro/mrboom-libretro.git
 [submodule "libretro/cores/gambatte/core"]
 	path = cores/gambatte/upstream
-	url = git@github.com:github.com/ehmry/gambatte-libretro.git
+	url = https://github.com/libretro/gambatte-libretro.git
 [submodule "libretro/cores/dinothawr/core"]
 	path = cores/dinothawr/core
 	url = https://github.com/libretro/Dinothawr
@@ -48,10 +48,10 @@
 	url = https://github.com/libretro/scummvm.git
 [submodule "libretro/cores/lutro/upstream"]
 	path = cores/lutro/upstream
-	url = git@github.com:ehmry/libretro-lutro.git
+	url = https://github.com/ehmry/libretro-lutro.git
 [submodule "libretro/cores/bluemsx/upstream"]
 	path = cores/bluemsx/upstream
-	url = git@github.com:ehmry/blueMSX-libretro.git
+	url = https://github.com/libretro/blueMSX-libretro.git
 [submodule "libretro/bios/cbios-cbios"]
 	path = bios/cbios-cbios
 	url = https://git.code.sf.net/p/cbios/cbios