tracing: Rename update the enum_map file

The enum_map file is used to display a list of symbol
to name conversions. As its now used to resolve sizeof
lets update the name and description.

Link: http://lkml.kernel.org/r/20170531215653.3240-13-jeremy.linton@arm.com



Signed-off-by: Jeremy Linton <jeremy.linton@arm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>