[devices] add generic-efi profile to be used for testing

Signed-off-by: Dan Johansen <strit@manjaro.org>

devices/generic-efi

+## Maintained by Strit ##
+## This "device" profile is for testing EFI compliance in our tools
+## Should not be used as a real profile
+
+# Kernel and bootloader stuff
+linux
+boot-generic
+efibootmgr
+plymouth
+plymouth-theme-manjaro
+
+# Video drivers
+
+# Other device specific packages
+crda
+btrfs-progs
+f2fs-tools
+generic-post-install