RFR (trivial): 8219814: Help-info for pns(...) on Linux/mips lost

[Jie Fu]

Hi all,

Bug:    https://bugs.openjdk.java.net/browse/JDK-8219814
Webrev: http://cr.openjdk.java.net/~jiefu/8219814/webrev.00/

When debug the VM in gdb and perform "call help()", the help-info for 
pns(...) on Linux/mips is lost.
However, it exists in jdk8.

To support debugging on as many platforms as possible, it would be 
better to keep it.

The patch has been tested on Linux/x86-64 and Loongson's Linux/mips64-port.
Could you please review it?
Thanks a lot.

Best regards,
Jie