generic/typesizes.h: Add support for 32-bit arches with 64-bit types

Update the default typesizes.h to match the new kernel sizes for 32-bit
architectures with a 64-bit time_t and friends. This follows the sizes
used for RV32 which is a y2038 safe architecture added after Linux 5.1.

Reviewed-by: Vineet Gupta <vgupta@synopsys.com>
Tested-by: Vineet Gupta <vgupta@synopsys.com>