ARM: dts: qcom: Modify adsp variant bits for lito target

ADSP variant uses 25 and 26 bits to identify the amount of
LPI memory and load the respective ADSP firmware images.
Modify the nvmem cell properties to accommodate this.
Add adsp-fw-names and adsp-fw-bit-values to use them
for identifying the ADSP fw image name to be loaded for
a sku variant.

Change-Id: Iab8a55906f6f4172b043970b6ff82595ca45de6e