powerpc/pnv: Avoid bogus output

There're couples of functions defined to print debugging messages
during initializing P7IOC. However, we got bogus output from those
functions like pe_info(). The problem here is that the message
level (the first parameter to printk()) isn't printable and that
caused the bogus output.

The patch fixes the issue by merging __pe_printk() to the macro
define_pe_printk_level() so that we can pass the message level
directly to printk().

Reported-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>