This patch adds function called "dap_detect_debug_base()", which should be
called to get location of the ROM Table. By walking ROM Table, it's possible to
discover the location of DAP.
Sadly, some CPUs misreport this value, therefore I had to introduce an fixup
table, which will be used in case such CPU is detected.
Signed-off-by: Marek Vasut <marek.vasut@gmail.com>