nvmem: core: Add stubs for nvmem_cell_read_variable_le_u32/64 if !CONFIG_NVMEM

nvmem: core: Add stubs for nvmem_cell_read_variable_le_u32/64 if !CONFIG_NVMEM

When I added nvmem_cell_read_variable_le_u32() and
nvmem_cell_read_variable_le_u64() I forgot to add the "static inline"
stub functions for when CONFIG_NVMEM wasn't defined. Add them
now. This was causing problems with randconfig builds that compiled
`drivers/soc/qcom/cpr.c`.

Fixes: 241f24365c20 ("PM: AVS: qcom-cpr: Use nvmem_cell_read_variable_le_u32()")
Fixes: fba1ba7395c3 ("nvmem: core: Add functions to make number reading easy")
Reported-by: kernel test robot <lkp@intel.com>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20210913160551.12907-1-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>