ShellPkg: acpiview: Add routine to print 16 chars

Certain ACPI tables like MPAM has fields which are 16 bytes long.
Routines similar to Dump12Chars but for 16 characters are required to
print such fields. Add Dump16Chars routine to satisfy this requirement.

Signed-off-by: Rohit Mathew <Rohit.Mathew@arm.com>
Change-Id: I1836cf64869603032acc32495087471cfdd97203
Cc: James Morse <james.Morse@arm.com>
Cc: Sami Mujawar <sami.mujawar@arm.com>
Cc: Thomas Abraham <thomas.abraham@arm.com>
Cc: Zhichao Gao <zhichao.gao@intel.com>
Reviewed-by: Pierre Gondois <pierre.gondois@arm.com>
Reviewed-by: Zhichao Gao <zhichao.gao@intel.com>
Reviewed-by: Sami Mujawar <sami.mujawar@arm.com>