Reduce ram origin

[martinwork]

This includes #51.

The ORIGIN value is the minimum required with the settings in microbit-foundation/codal-microbit-nrf5sdk#12.

[finneyj]

Thanks @martinwork.

Can you just briefly give rationale here? It looks like we've slightly increased the GATT table size, but significantly reduced the RAM origin? How is it that we're reclaiming a lot of memory from the GATT table region, yet also apparently increasing the GATT table size?

Is this is throwback from when we switched to a different version of soft device? or are we configuring a smaller GATT table somewhere?

[martinwork]

Yes, it's because I forgot to minimise the RAM ORIGIN when we switched to S113, otherwise it would need to be increased again to allow for https://github.com/microbit-foundation/codal-microbit-nrf5sdk/pull/12/files, as it would if we were still using S140.

Add the definitions below to get the SDK to DMESG the ORIGIN/RAM start possible after softdevice's share. e.g.:
nrf_sdh_ble: RAM starts at 0x20002440
nrf_sdh_ble: RAM start location can be adjusted to 0x20001F60.
nrf_sdh_ble: RAM size for application can be adjusted to 0x1E0A0.

softdevice's RAM requirement are affected by NRF_SDH_BLE_GATTS_ATTR_TAB_SIZE and NRF_SDH_BLE_VS_UUID_COUNT:
https://github.com/microbit-foundation/codal-microbit-nrf5sdk/blob/master/sdk_config/sdk_config.h#L4540

Settings for codal.json to report RAM usage in
https://github.com/microbit-foundation/codal-microbit-nrf5sdk/blob/master/nRF5SDK/components/softdevice/common/nrf_sdh_ble.c#L229

        "DEVICE_DMESG_BUFFER_SIZE":2048,
        "DMESG_SERIAL_DEBUG":1,

        "MICROBIT_DMESG_LEVEL" : 0,

        "NRF_LOG_BACKEND_DMESG_ENABLED" : 1,
        "NRF_LOG_BACKEND_DMESG_FLUSH" : 1,

        "NRF_LOG_ENABLED" : 1,
        "NRF_LOG_DEFERRED" : 0,
        "NRF_LOG_DEFAULT_LEVEL": 4,
        
        "NRF_SDH_BLE_LOG_ENABLED": 1,
        "NRF_SDH_BLE_LOG_LEVEL": 4

Other SDK debug settings:

        "NRF_SDH_LOG_ENABLED": 1,
        "NRF_SDH_LOG_LEVEL": 4,

        "NRF_SDH_SOC_LOG_ENABLED": 1,
        "NRF_SDH_SOC_LOG_LEVEL": 4,

        "PM_LOG_ENABLED": 1,
        "PM_LOG_LEVEL": 4,

        "NRF_PWR_MGMT_CONFIG_LOG_ENABLED": 1,
        "NRF_PWR_MGMT_CONFIG_LOG_LEVEL": 4

[finneyj]

OK - thanks @martinwork!

I trust your analysis, just wanted to check the rationale.
No-one would thank you for creating an unstable BSS/HEAP region . :)