coresight: Remove %px for printing pcsr value

The driver prints pcsr twice: the first time it uses specifier %px to
print hexadecimal pcsr value and the second time uses specifier %pS for
output kernel symbols.

As suggested by Kees, using %pS should be sufficient and %px isn't
necessary; the reason is if the pcsr is a kernel space address, we can
easily get to know the code line from %pS format, on the other hand, if
the pcsr value doesn't fall into kernel space range (e.g. if the CPU is
stuck in firmware), %pS also gives out pcsr hexadecimal value.

So this commit removes useless %px and update section "Output format"
in the document for alignment between the code and document.

Suggested-by: Kees Cook <keescook@chromium.org>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>