device-drivers: pci: check memory region for flag IORESOURCE_PREFETCH

This is done to make sure there will be no side effects if we change it somehow
in the test (e.g. we're not changing I/O ports implemented as memory regions).
Remove annoying printk messages.

Signed-off-by: Alexey Kodanev <alexey.kodanev@oracle.com>
Reviewed-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>