drm/xe/xe2hpg: Determine flat ccs offset for vram

on Xe2 dgfx platform determine the offset using Flat CCS size
bitfield of XE2_FLAT_CCS_BASE_RANGE_[UPPER/LOWER] mcr registers.

v2: function argument tile_size changed from pass by reference to pass
by value

Bspec: 68023
Signed-off-by: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
Signed-off-by: Akshata Jahagirdar <akshata.jahagirdar@intel.com>
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Signed-off-by: Balasubramani Vivekanandan <balasubramani.vivekanandan@intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240408170545.3769566-7-balasubramani.vivekanandan@intel.com