nimble/l2cap: Fix for L2CAP connection parameters update
nimble/l2cap: Fix for L2CAP connection parameters update

If GAP does not accept parameters (core spec requirements),
BLE_L2CAP_SIG_OP_UPDATE_RSP with a reason
BLE_L2CAP_SIG_UPDATE_RSP_RESULT_REJECT shell be sent back to the
remote device.

This patch fixes PTS test cases TC_LE_CPU_BI_01_C,TC_LE_CPU_BV_02_C.

mlaz/mynewt-core,IMGJulian/incubator-mynewt-core,andrzej-kaczmarek/apache-mynewt-core,IMGJulian/incubator-mynewt-core,andrzej-kaczmarek/apache-mynewt-core,mlaz/mynewt-core,andrzej-kaczmarek/incubator-mynewt-core,andrzej-kaczmarek/apache-mynewt-core,wes3/incubator-mynewt-core,wes3/incubator-mynewt-core,wes3/incubator-mynewt-core,andrzej-kaczmarek/incubator-mynewt-core,IMGJulian/incubator-mynewt-core,IMGJulian/incubator-mynewt-core,andrzej-kaczmarek/incubator-mynewt-core,mlaz/mynewt-core,andrzej-kaczmarek/incubator-mynewt-core,mlaz/mynewt-core,mlaz/mynewt-core,andrzej-kaczmarek/incubator-mynewt-core,andrzej-kaczmarek/apache-mynewt-core,wes3/incubator-mynewt-core,IMGJulian/incubator-mynewt-core,wes3/incubator-mynewt-core