Add Rasperry Pi WiFi support

We need the Broadcom firmware from the _linux-firmware_ package (and
nothing else).  We also need _wpa_supplicant_, to configure the WiFi
connection.  Finally, we need to configure _systemd-networkd_ to manage
the network device.

install.packages

@@ -0,0 +1 @@
+net-wireless/wpa_supplicant

installonly.packages

@@ -0,0 +1 @@
+sys-kernel/linux-firmware

overlay/etc/aimee-os/writable-etc

@@ -0,0 +1 @@
+d wpa_supplicant

overlay/etc/systemd/network/95-default.network

@@ -0,0 +1,11 @@
+[Match]
+Type=ether wlan
+
+[Network]
+DHCP=yes
+
+[DHCPv4]
+UseDomains=yes
+
+[DHCPv6]
+UseDomains=yes

portage/package.license/linux-firmware

@@ -0,0 +1 @@
+sys-kernel/linux-firmware linux-fw-redistributable

portage/savedconfig/sys-kernel/linux-firmware

@@ -0,0 +1,17 @@
+# symlink targets have to be specified explicity
+../cypress/cyfmac43455-sdio.bin
+../cypress/cyfmac43455-sdio.clm_blob
+
+brcm/brcmfmac43455-sdio.AW-CM256SM.txt
+brcm/brcmfmac43455-sdio.MINIX-NEO Z83-4.txt
+brcm/brcmfmac43455-sdio.Raspberry Pi Foundation-Raspberry Pi 4 Model B.txt
+brcm/brcmfmac43455-sdio.Raspberry Pi Foundation-Raspberry Pi Compute Module 4.txt
+brcm/brcmfmac43455-sdio.acepc-t8.txt
+brcm/brcmfmac43455-sdio.beagle,am5729-beagleboneai.txt
+brcm/brcmfmac43455-sdio.bin
+brcm/brcmfmac43455-sdio.clm_blob
+brcm/brcmfmac43455-sdio.raspberrypi,3-model-a-plus.txt
+brcm/brcmfmac43455-sdio.raspberrypi,3-model-b-plus.txt
+brcm/brcmfmac43455-sdio.raspberrypi,4-model-b.txt
+cypress/cyfmac43455-sdio.bin
+cypress/cyfmac43455-sdio.clm_blob