Bluetooth: fix kernel oops in store_pending_adv_report

Fix kernel oops observed when an ext adv data is larger than 31 bytes.

This can be reproduced by setting up an advertiser with advertisement
larger than 31 bytes.  The issue is not sensitive to the advertisement
content.  In particular, this was reproduced with an advertisement of
229 bytes filled with 'A'.  See stack trace below.

This is fixed by not catching ext_adv as legacy adv are only cached to
be able to concatenate a scanable adv with its scan response before
sending it up through mgmt.

With ext_adv, this is no longer necessary.

Taken from https://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth-next.git/commit/?id=a2ec905d1e160a33b2e210e45ad30445ef26ce0e
By Linus Torvalds <torvalds@linux-foundation.org>

Change-Id: Iad1e016df8e034318c9bd197aaeae4ba712cc99f