tools lib traceevent: Check for spaces in character array

tools lib traceevent: Check for spaces in character array

Currently when using the raw format for fields, when looking at a
character array, to determine if it is a string or not, we make sure all
characters are "isprint()". If not, then we consider it a numeric array,
and print the hex numbers of the characters instead.

But it seems that '\n' fails the isprint() check! Add isspace() to the
check as well, such that if all characters pass isprint() or isspace()
it will assume the character array is a string.

Reported-by: Xenia Ragiadakou <burzalodowa@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Xenia Ragiadakou <burzalodowa@gmail.com>
Link: http://lkml.kernel.org/r/20131101215501.465091682@goodmis.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>