Doc: Add git and base-devel to MSYS2 dependencies

"git" is obviously needed for pulling the latest source code.

"base-devel" is needed to actually make the compiler toolchain work.

Both packages are not installed in current MSYS2 base installations.

README.md

@@ -136,11 +136,11 @@ To build on Windows for development, using MSYS2 is recommended. Follow the inst
 
 For x86 (32 bit) builds:
 
-	pacman -Sy mingw-w64-i686-{cmake,ffmpeg,gcc,gdb,imagemagick,libelf,libepoxy,libzip,pkg-config,qt5,SDL2,ntldd-git}
+	pacman -Sy base-devel git mingw-w64-i686-{cmake,ffmpeg,gcc,gdb,imagemagick,libelf,libepoxy,libzip,pkg-config,qt5,SDL2,ntldd-git}
 
 For x86_64 (64 bit) builds:
 
-	pacman -Sy mingw-w64-x86_64-{cmake,ffmpeg,gcc,gdb,imagemagick,libelf,libepoxy,libzip,pkg-config,qt5,SDL2,ntldd-git}
+	pacman -Sy base-devel git mingw-w64-x86_64-{cmake,ffmpeg,gcc,gdb,imagemagick,libelf,libepoxy,libzip,pkg-config,qt5,SDL2,ntldd-git}
 
 Check out the source code by running this command:
 

README_DE.md

@@ -136,11 +136,11 @@ Um mGBA auf Windows zu kompilieren, wird MSYS2 empfohlen. Befolge die Installati
 
 Für x86 (32 Bit):
 
-	pacman -Sy mingw-w64-i686-{cmake,ffmpeg,gcc,gdb,imagemagick,libelf,libepoxy,libzip,pkg-config,qt5,SDL2,ntldd-git}
+	pacman -Sy base-devel git mingw-w64-i686-{cmake,ffmpeg,gcc,gdb,imagemagick,libelf,libepoxy,libzip,pkg-config,qt5,SDL2,ntldd-git}
 
 Für x86_64 (64 Bit):
 
-	pacman -Sy mingw-w64-x86_64-{cmake,ffmpeg,gcc,gdb,imagemagick,libelf,libepoxy,libzip,pkg-config,qt5,SDL2,ntldd-git}
+	pacman -Sy base-devel git mingw-w64-x86_64-{cmake,ffmpeg,gcc,gdb,imagemagick,libelf,libepoxy,libzip,pkg-config,qt5,SDL2,ntldd-git}
 
 Lade den aktuellen mGBA-Quellcode mithilfe des folgenden Kommandos herunter: