Updates in memdisk paths in EFI images generation

Prepares "gen-efi" script for transition to the new
grub2-mkstandalone --install-modules="..." capability
(Savannah: #36772).
Updated laptop-mode-tools configuration

Also fixed the non-drive-waking hdparm patch.
Initial XChat -> HexChat configuration migration
Updated firmware included for RT2800PCI

rt2800pci_get_firmware_name returns firmware conditionally
in drivers/net/wireless/rt2x00/rt2800pci.c.
Re-enabled NUMA support in sys-apps/irqbalance (#456238)
Added USE=gpm back to default settings
Disabled /usr/sbin/alsaconf exclusion due to updated alsa-utils
Disabled unnecessary OpenType support in libass subtitles renderer