[EGD-2501] Add gsm powerdown due to battery

Gsm model power state maintenance based on battery level.

[EGD-5186] Change minimum CPU frequency to 132 MHz

Temporary minimum CPU frequency limitation

[EGD-4887] Add PLL2 clock switching

Pll2 will be disabled at the lowest CPU frequency,
which will save power

[EGD-4881] Add oscillator clock switching mechanisms

Osc will change automatically at the lowest CPU frequency,
which will save power

[EGD-5050] Add brownout detection

Brownout detectection realized through charger driver

[EGD-4694] Add CPU frequency shift mechanism

The CPU frequency changes automatically which saves energy

[EGD-4952] Fixes for rt1051

[EGD-4952] Added critical level check + messages

[EGD-4696] Several stabilization patches. (#1192)

Merge branch 'master' into stable

[EGD-4693] PowerManagement: CPU load measurement (#1156)

Add FreeRTOS idle tasks Run Time Statistics

This will allow to measure the CPU load

Merge branch 'master' into stable

[EGD-4472] PowerManagement: Separation of CPU clock into separate clock domain (#1125)

Change CPU clock into separate clock domain

We can control the CPU frequency independently of the peripherals.

[EGD-4477] Dump logs to a file for linux (#1081)

[EGD-4477] Implement dumping logs to a file for linux

[EGD-4219] Convert service-evtmgr and service-lwip to library

[EGD-4200] Message handling refactored. (#974)

[EGD-4288] refactor global data (#959)

Reduce firmware size by refactoring global data defined in public
headers.

Each global variable which require runtime initialization adds
initialization code to every translation unit which includes the header
where the variable is defined and declared.

[EGD-3743] Removed old doxygen copyright statements from project.

[EGD-3743] Update copyrights in fies

[EGD-3854] Removing goto's from the code (#797)

It is generic cleanup task for removing all goto files

Co-authored-by: Lucjan Bryndza <lucjan.bryndza@mudita.com>