rpi-cmdline: Fix being renamed of network interfaces

Add net.ifnames=0 kernel parameter into CMDLINE and make it possible to override.

If we boot the kernel this way, the network interfaces will not be renamed. Otherwise it will be renamed.

Without parameter:

root@raspberrypi3-64:~# ip addr
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host noprefixroute
       valid_lft forever preferred_lft forever
2: enu1u1: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc fq_codel qlen 1000
    link/ether b8:27:eb:d9:fd:59 brd ff:ff:ff:ff:ff:ff
3: wlxb827eb8ca80c: <BROADCAST,MULTICAST> mtu 1500 qdisc noop qlen 1000
    link/ether b8:27:eb:8c:a8:0c brd ff:ff:ff:ff:ff:ff

root@raspberrypi3-64:~# journalctl | grep wlan
Feb 27 17:26:08 raspberrypi3-64 kernel: brcmfmac mmc1:0001:1 wlxb827eb8ca80c: renamed from wlan0
Feb 27 17:26:10 raspberrypi3-64 kernel[296]: [    8.711897] brcmfmac mmc1:0001:1 wlxb827eb8ca80c: renamed from wlan0

With parameter:

root@raspberrypi3-64:~# ip addr
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host noprefixroute
       valid_lft forever preferred_lft forever
2: eth0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc fq_codel qlen 1000
    link/ether b8:27:eb:d9:fd:59 brd ff:ff:ff:ff:ff:ff
3: wlan0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc fq_codel qlen 1000
    link/ether b8:27:eb:8c:a8:0c brd ff:ff:ff:ff:ff:ff

Signed-off-by: alperak <alperyasinak1@gmail.com>

Author: alperak

recipes-bsp/bootfiles/rpi-cmdline.bb

@@ -46,6 +46,9 @@ CMDLINE_ISOL_CPUS ?= "${@setup_isolcpus(d)}"
 # if the MAC addresses are omitted, random values will be used
 CMDLINE_RNDIS ?= ""
 
+# That allows to keep the traditional network interface names
+CMDLINE_IFNAMES ?= "net.ifnames=0"
+
 CMDLINE = " \
     ${CMDLINE_ISOL_CPUS} \
     ${CMDLINE_DWC_OTG} \
@@ -57,6 +60,7 @@ CMDLINE = " \
     ${CMDLINE_PITFT} \
     ${CMDLINE_DEBUG} \
     ${CMDLINE_RNDIS} \
+    ${CMDLINE_IFNAMES} \
     "
 
 do_compile() {