ShellPkg: update ping6 to use timer service instead of timer arch protocol .

This patch update the shell ping command to use timer service to calculate the
RTT time, instead of using the timer arch protocol.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Zhang Lubo <lubo.zhang@intel.com>
Cc: Ni Ruiyu <ruiyu.ni@intel.com>
Cc: Ye Ting <ting.ye@intel.com>
Cc: Fu Siyuan <siyuan.fu@intel.com>
Reviewed-by: Fu Siyuan <siyuan.fu@intel.com>

ShellPkg/Library/UefiShellNetwork2CommandsLib/UefiShellNetwork2CommandsLib.inf

@@ -55,6 +55,7 @@
 
 [Protocols]
   gEfiCpuArchProtocolGuid                       ## CONSUMES
+  gEfiTimerArchProtocolGuid
   gEfiIp6ProtocolGuid                           ## SOMETIMES_CONSUMES
   gEfiIp6ServiceBindingProtocolGuid             ## SOMETIMES_CONSUMES
   gEfiIp6ConfigProtocolGuid                     ## SOMETIMES_CONSUMES