[8] RFR (S) 8033251: Use DWARF debug symbols for Linux 32-bit as default

[David Buck]

Hi!

May I please get a review of this simple backport to replace stabs with 
DWARF for 32-bit Linux builds. This is needed as newer toolchains no 
longer support stabs.

bug report:
https://bugs.openjdk.java.net/browse/JDK-8033251

JDK 9 changeset:
http://hg.openjdk.java.net/jdk9/jdk9/hotspot/rev/2750fb4ad9ac

JDK 8 webrev for review:
http://cr.openjdk.java.net/~dbuck/8033251.0/

Cheers,
-Buck