Fix : Multiple advertising feature was not working

Fix : Multiple advertising feature was not working

[Problem] Multiple advertising feature was not working
[Cause & Measure] Advertising slot was not initialized because BT
chipset supported slot count is over the defined maximum. Platform can
support the large number of slots if BT chipset can. So we don't need
to define maximum value of slots. This patch removes the maximum value
of slots.
[Checking Method] Turn on Bluetooth and check advertising slot's
initialization.

Change-Id: Ic0a3293b4f4e7f7b048b61074fb95b9898efba7e