[PATCH] Fix for hotspot build failures on Linux

[Kaushik Srenevasan]

I'm running into build failures while trying to build hotspot (only -
not the JDK). It looks like the first of these is due to a change
introduced in 2558:81d815b05abb while the second has been around
forever.

hotspot/src/share/vm/oops/constantPoolOop.cpp:272:40: error:
converting 'false' to pointer type 'methodOop'
[-Werror=conversion-null]
hotspot/src/share/vm/opto/loopnode.cpp:896:50: error: converting
'false' to pointer type 'Node*' [-Werror=conversion-null]

The cause for both of these is a conversion from bool to a pointer
type conversion warning being treated as an error; that gcc (Debian
4.7.1-2) 4.7.1 doesn't seem to like.

Attached patch fixes this.

Thanks,
         -Kaushik

PS: FWIW, here's the command I'm using to build:
make LANG=C ARCH_DATA_MODEL=64 DISABLE_HOTSPOT_OS_VERSION_CHECK=ok
ALT_BOOTDIR=/usr/lib/jvm/java-1.6.0-openjdk-amd64 jvmg