wireless-regdb: Add 5725-5875 MHz rule for Portugal (PT) According to [1], SRD devices in this range are allowed in Portugal, as specified in this document (page 56), and in compliance with ETSI EN 300 440-1. [1] https://www.anacom.pt/streaming/25.5_10.000mhz.pdf?contentId=271706&field=ATTACHED_FILE Signed-off-by: Rui Salvaterra <rsalvaterra@gmail.com> Signed-off-by: Seth Forshee <seth.forshee@canonical.com>