Bluetooth: Add l2cap-send command to btshell
Bluetooth: Add l2cap-send command to btshell

l2cap-send can be used to send data when connecting to an L2CAP channel:

btshell> l2cap-send 3
bt: bt_l2cap_chan_send (0x00114b0c): chan 0x00112824 buf 0x00112b00 len 23
bt: l2cap_chan_create_seg (0x00114b0c): chan 0x00112824 seg 0x001124f8 len 23
bt: l2cap_chan_le_send (0x00114b0c): chan 0x00112824 cid 0x0040 len 23 credits 7
bt: l2cap_chan_le_send (0x00114b0c): chan 0x00112824 cid 0x0040 len 2 credits 6
bt: bt_l2cap_chan_send (0x00114b0c): chan 0x00112824 buf 0x00112b00 len 23
bt: l2cap_chan_create_seg (0x00114b0c): chan 0x00112824 seg 0x001124f8 len 23
bt: l2cap_chan_le_send (0x00114b0c): chan 0x00112824 cid 0x0040 len 23 credits 5
bt: l2cap_chan_le_send (0x00114b0c): chan 0x00112824 cid 0x0040 len 2 credits 4
bt: bt_l2cap_chan_send (0x00114b0c): chan 0x00112824 buf 0x00112b00 len 23
bt: l2cap_chan_create_seg (0x00114b0c): chan 0x00112824 seg 0x001124f8 len 23
bt: l2cap_chan_le_send (0x00114b0c): chan 0x00112824 cid 0x0040 len 23 credits 3
bt: l2cap_chan_le_send (0x00114b0c): chan 0x00112824 cid 0x0040 len 2 credits 2

Change-Id: Ibc970d1ffd8c407c66b35e9f3bf49ccf826f7472
Signed-off-by: Luiz Augusto von Dentz <8530c5ea66a1bdbc08f98bfcf183c8be901b5990@intel.com>

ldts/zephyr,mirzak/zephyr-os,bigdinotech/zephyr,fractalclone/zephyr-riscv,Vudentz/zephyr,pklazy/zephyr,32bitmicro/zephyr,mirzak/zephyr-os,aceofall/zephyr-iotos,bboozzoo/zephyr,runchip/zephyr-cc3200,bboozzoo/zephyr,pklazy/zephyr,explora26/zephyr,kraj/zephyr,punitvara/zephyr,jamesonwilliams/zephyr-kernel,coldnew/zephyr-project-fork,fractalclone/zephyr-riscv,mbolivar/zephyr,jamesonwilliams/zephyr-kernel,Vudentz/zephyr,erwango/zephyr,ldts/zephyr,rsalveti/zephyr,zephyriot/zephyr,aceofall/zephyr-iotos,runchip/zephyr-cc3220,32bitmicro/zephyr,mbolivar/zephyr,zephyriot/zephyr,runchip/zephyr-cc3220,mirzak/zephyr-os,rsalveti/zephyr,explora26/zephyr,jamesonwilliams/zephyr-kernel,coldnew/zephyr-project-fork,galak/zephyr,GiulianoFranchetto/zephyr,erwango/zephyr,fbsder/zephyr,ldts/zephyr,GiulianoFranchetto/zephyr,tidyjiang8/zephyr-doc,nashif/zephyr,galak/zephyr,coldnew/zephyr-project-fork,coldnew/zephyr-project-fork,fractalclone/zephyr-riscv,explora26/zephyr,mbolivar/zephyr,zephyrproject-rtos/zephyr,Vudentz/zephyr,runchip/zephyr-cc3220,tidyjiang8/zephyr-doc,explora26/zephyr,zephyriot/zephyr,erwango/zephyr,pklazy/zephyr,fbsder/zephyr,rsalveti/zephyr,explora26/zephyr,mirzak/zephyr-os,ldts/zephyr,aceofall/zephyr-iotos,galak/zephyr,32bitmicro/zephyr,punitvara/zephyr,jamesonwilliams/zephyr-kernel,punitvara/zephyr,tidyjiang8/zephyr-doc,erwango/zephyr,kraj/zephyr,finikorg/zephyr,tidyjiang8/zephyr-doc,bigdinotech/zephyr,aceofall/zephyr-iotos,fractalclone/zephyr-riscv,tidyjiang8/zephyr-doc,runchip/zephyr-cc3200,fbsder/zephyr,runchip/zephyr-cc3220,pklazy/zephyr,finikorg/zephyr,bigdinotech/zephyr,mirzak/zephyr-os,ldts/zephyr,bboozzoo/zephyr,runchip/zephyr-cc3200,bboozzoo/zephyr,32bitmicro/zephyr,mbolivar/zephyr,zephyrproject-rtos/zephyr,fbsder/zephyr,zephyriot/zephyr,kraj/zephyr,sharronliu/zephyr,bigdinotech/zephyr,jamesonwilliams/zephyr-kernel,runchip/zephyr-cc3200,holtmann/zephyr,nashif/zephyr,fbsder/zephyr,bigdinotech/zephyr,Vudentz/zephyr,holtmann/zephyr,zephyrproject-rtos/zephyr,GiulianoFranchetto/zephyr,nashif/zephyr,finikorg/zephyr,coldnew/zephyr-project-fork,GiulianoFranchetto/zephyr,zephyriot/zephyr,erwango/zephyr,runchip/zephyr-cc3220,zephyrproject-rtos/zephyr,holtmann/zephyr,runchip/zephyr-cc3200,finikorg/zephyr,rsalveti/zephyr,finikorg/zephyr,kraj/zephyr,sharronliu/zephyr,fractalclone/zephyr-riscv,holtmann/zephyr,galak/zephyr,aceofall/zephyr-iotos,Vudentz/zephyr,Vudentz/zephyr,punitvara/zephyr,kraj/zephyr,sharronliu/zephyr,GiulianoFranchetto/zephyr,nashif/zephyr,galak/zephyr,pklazy/zephyr,punitvara/zephyr,rsalveti/zephyr,nashif/zephyr,sharronliu/zephyr,holtmann/zephyr,sharronliu/zephyr,mbolivar/zephyr,32bitmicro/zephyr,bboozzoo/zephyr,zephyrproject-rtos/zephyr