SWDEV-271363 - Fix undefined HIP_VERSION_GITDATE
SWDEV-271363 - Fix undefined HIP_VERSION_GITDATE

HIP_VERSION_GITDATE won't be defined when git isn't
installed. This will lead to building failure of
deviceLib.hipVersion. When git isn't installed, set
HIP_VERSION_GITDATE as 0 by default.

Change-Id: Icf5763449ccec833d9efda90ffe3a86fb53bdb82

ROCm-Developer-Tools/HIP,ROCm-Developer-Tools/HIP,ROCm-Developer-Tools/HIP,ROCm-Developer-Tools/HIP,ROCm-Developer-Tools/HIP