powerpc/pseries/lparcfg: drop error message from guest name lookup

powerpc/pseries/lparcfg: drop error message from guest name lookup

It's not an error or exceptional situation when the hosting
environment does not expose a name for the LP/guest via RTAS or the
device tree. This happens with qemu when run without the '-name'
option. The message also lacks a newline. Remove it.

Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Fixes: eddaa9a40275 ("powerpc/pseries: read the lpar name from the firmware")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240524-lparcfg-updates-v2-1-62e2e9d28724@linux.ibm.com