Simplify if statement when auto detect houdini ABI
Simplify if statement when auto detect houdini ABI

CMake will implicitly check for the -NOTFOUND suffix and return false.

Signed-off-by: Fredrik Salomonsson <94092975b04047b37821994781a0b9ea8d41c3ff@d2.com>

dreamworksanimation/openvdb,dreamworksanimation/openvdb,dreamworksanimation/openvdb,dreamworksanimation/openvdb