mcp251xfd-dump: add tool to decode chip and driver state of mcp251xfd

It works on dev coredump data generated by the mcp251xfd driver in
case of failures, as well as on regmap based register dumps.

Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

.gitignore

@@ -20,6 +20,7 @@ GNUmakefile.in
 /config/m4/ltsugar.m4
 /config/m4/ltversion.m4
 /config/m4/lt~obsolete.m4
+/mcp251xfd/.dirstamp
 
 /asc2log
 /bcmserver
@@ -47,6 +48,7 @@ GNUmakefile.in
 /j1939sr
 /log2asc
 /log2long
+/mcp251xfd-dump
 /slcan_attach
 /slcand
 /slcanpty