MFC r315780:

[iwm] Remove a couple of unneeded IWM_UCODE_TLV_FLAGS_* flags.

• All the supported firmwares have these flags set.

• This removes the following flags: IWM_UCODE_TLV_FLAGS_PM_CMD_SUPPORT, IWM_UCODE_TLV_FLAGS_NEWBT_COEX, IWM_UCODE_TLV_FLAGS_BF_UPDATED, IWM_UCODE_TLV_FLAGS_D3_CONTINUITY_API, IWM_UCODE_TLV_FLAGS_STA_KEY_CMD, IWM_UCODE_TLV_FLAGS_DEVICE_PS_CMD, IWM_UCODE_TLV_FLAGS_SCHED_SCAN, IWM_UCODE_TLV_FLAGS_RX_ENERGY_API, IWM_UCODE_TLV_FLAGS_TIME_EVENT_API_V2

• Also remove definitions and code for dealing with the v1 time-event api.

• Remove unneeded calc_rssi() function.