onboardingcodes now requires rendezvous type (#12963)
onboardingcodes now requires rendezvous type (#12963)

The shell's "onboardingcodes" could only generate codes with the BLE
rendezvous flag set.  It was hardcoded.

This commit adds a required first parameter to the "onboardingcodes"
command: none|softap|ble|onnetwork.  The help screen was also updated.

The motivation for this change was so I could generate a correct QR code
for IP commissioning.
project-chip/connectedhomeip,project-chip/connectedhomeip,project-chip/connectedhomeip,nestlabs/connectedhomeip,nestlabs/connectedhomeip,project-chip/connectedhomeip,nestlabs/connectedhomeip,nestlabs/connectedhomeip,project-chip/connectedhomeip,nestlabs/connectedhomeip,project-chip/connectedhomeip,nestlabs/connectedhomeip,nestlabs/connectedhomeip