v2.0-rc1

Version 2.0-rc1
Added common description for shared memory physical address range parameter

Added SBI debug console extension

Relaxed the counter width requirement on SBI PMU firmware counters

Added sbi_pmu_counter_fw_read_hi() in SBI PMU extension

Reserved space for SBI implementation specific firmware events

Added SBI system suspend extension

Added SBI CPPC extension

Clarified that an SBI extension can be partially implemented only if it defines a mechanism to discover implemented SBI functions

Added error code SBI_ERR_NO_SHMEM

Added SBI nested acceleration extension

Added common description for a virtual HART

Added SBI steal-time accounting extension

Added SBI PMU snapshot extension