soc: intel: adsp: tgl: ace: Set correct virtual memory size

Corrected virtual memory size to match the range supported by the
Translation Lookup Buffer. The TLB size is 16 MB, however the first 128 KB
is dedicated to LPSRAM and bypasses the TLB. This was taken into account in
KERNEL_VM_BASE, so KERNEL_VM_SIZE was reduced accordingly.

Signed-off-by: Adrian Warecki <adrian.warecki@intel.com>