target: restructure dap support

- add 'dap create' command to create dap instances
- move all dap subcmmand into the dap instance commands
- keep 'dap info' for convenience
- change all armv7 and armv8 targets to take a dap
  instance instead of a jtag chain position
- restructure tap/dap/target relations, jtag tap no
  longer references the dap, daps are now independently
  created and initialized.
- clean up swd connect
- re-initialize DAP also on JTAG errors (e.g. after reset,
  power cycle)
- update documentation
- update target files

Change-Id: I322cf3969b5407c25d1d3962f9d9b9bc1df067d9
Signed-off-by: Matthias Welwarsky <matthias.welwarsky@sysgo.com>
Reviewed-on: http://openocd.zylin.com/4468
Tested-by: jenkins
Reviewed-by: Matthias Welwarsky <matthias@welwarsky.de>

tcl/target/xilinx_ultrascale.cfg

@@ -17,7 +17,8 @@ if { [info exists DAP_TAPID] } {
     set _DAP_TAPID 0x5ba00477
 }
 
-jtag newtap $_CHIPNAME dap -irlen 4 -ircapture 0x1 -irmask 0xf -expected-id $_DAP_TAPID
+jtag newtap $_CHIPNAME tap -irlen 4 -ircapture 0x1 -irmask 0xf -expected-id $_DAP_TAPID
+dap create $_CHIPNAME.dap -chain-position $_CHIPNAME.tap
 
 #
 # PS tap
@@ -53,6 +54,7 @@ jtag configure $_CHIPNAME.ps -event setup {
 
 set _TARGETNAME $_CHIPNAME.a53
 set _CTINAME $_CHIPNAME.cti
+set _smp_command ""
 
 set DBGBASE {0x80410000 0x80510000 0x80610000 0x80710000}
 set CTIBASE {0x80420000 0x80520000 0x80620000 0x80720000}
@@ -60,10 +62,10 @@ set _cores 4
 
 for { set _core 0 } { $_core < $_cores } { incr _core } {
 
-    cti create $_CTINAME.$_core -chain-position $_CHIPNAME.dap -ap-num 1 \
+    cti create $_CTINAME.$_core -dap $_CHIPNAME.dap -ap-num 1 \
         -ctibase [lindex $CTIBASE $_core]
 
-    set _command "target create $_TARGETNAME.$_core aarch64 -chain-position $_CHIPNAME.dap \
+    set _command "target create $_TARGETNAME.$_core aarch64 -dap $_CHIPNAME.dap \
         -dbgbase [lindex $DBGBASE $_core] -cti $_CTINAME.$_core"
 
     if { $_core != 0 } {