libnm,core: fix device TYPE for Wi-Fi P2P devices

Don't use "wifip2p" for the type description.

    $ nmcli device
    DEVICE             TYPE      STATE         CONNECTION
    wlan0              wifi      connected     x
    p2p-dev-wlan0      wifip2p   disconnected  --

!87
(cherry picked from commit 8f6a8d05)
4 jobs for nm-1-16
Status Job ID Name Coverage
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canceled #139199
build_f28

canceled #139200
build_f_latest

canceled #139201
allowed to fail
build_f_rawhide

canceled #139198
allowed to fail
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