Bluetooth: shell: Fix ifdef order in command inclusion

Fix ifdef in command inclusion, in practice this meant that
CONFIG_BT_LL_SW_SPLIT and CONFIG_BT_CTLR_ADV_EXT switched meaning.
Added blank lines so that the commands in shell/ll.c are more
easily visible as group.

Signed-off-by: Joakim Andersson <joakim.andersson@nordicsemi.no>