GUI: Add ability to force DPI scaling via config #44

Job	Run time
Windows (win32, x86-windows, x86, --enable-discord --enable-faad --enable-gif --enable-mikmod --e...	24m 23s
Windows (x64, x64, x64-windows, --enable-discord --enable-faad --enable-gif --enable-mikmod --ena...	22m 44s
Ubuntu (ubuntu-latest, sdl2-config, ccache g++, liba52-dev libcurl4-openssl-dev libfaad-dev libfl...	26m 43s
Xcode (macosx, -scheme ScummVM-macOS, --disable-nasm --enable-faad --enable-gif --enable-mikmod -...	26m 52s
Windows (arm64, arm64, arm64-windows, --enable-discord --enable-faad --enable-gif --enable-mikmod...	53m 27s
Ubuntu (ubuntu-20.04, sdl-config, ccache g++-4.8, g++-4.8 liba52-dev libcurl4-openssl-dev libfaad...	21m 58s
Xcode (ios7, -scheme ScummVM-iOS CODE_SIGN_IDENTITY="" CODE_SIGNING_ALLOWED=NO, --use-xcframework...	23m 31s
	3h 19m 38s

Provide feedback