l2cap: Upper tester implementation

This upper tester implemetation is dedicated to
L2CAP/FOC/BV-04-C and L2CAP/FOC/BV-05-C

where it is expected that Android will change in rounds FCS options.
As by default Android uses FCS Option 0x01 when needed, but above
testcases also verifies different configuration.
Therefore there is a need to implement Upper Tester for those test cases

To enable Upper tester for test case BV-04 following prop needs to be
set to 4

setprop bluetooth.pts.l2cap.foc.bv.test 4

if test case BV-05-C is executed it should be

bluetooth.pts.l2cap.foc.bv.test 5

Bug: 371948052
Flag: Exempt, test only behind the define
Test: mmm packages/modules/Bluetooth
Test: manual PTS testcases
Change-Id: I6aadc1792dcc4f75af988ca9945bb439efd21b88