Remove ManagedNamespace header and cleanup some math utils.

[andy31415]

Cleanup towards minimal dependencies in weave message layer.
Managed namespace header is not used at all and removed all non-inline
math util method declarations.

[github-actions]

Size increase report for "nrf-example-build"

File	Section	File	VM

Full report output

BLOAT REPORT

Files found only in the build output:
    report.csv

Comparing ./master_artifact/chip-nrf52840-lock-example.out and ./pull_artifact/chip-nrf52840-lock-example.out:

sections,vmsize,filesize

[github-actions]

Size increase report for "nrfconnect-example-build"

File	Section	File	VM

Full report output

BLOAT REPORT

Files found only in the build output:
    report.csv

Comparing ./master_artifact/chip-nrf52840-lock-example.elf and ./pull_artifact/chip-nrf52840-lock-example.elf:

sections,vmsize,filesize

[github-actions]

Size increase report for "linux-example-build"

File	Section	File	VM

Full report output

BLOAT REPORT

Files found only in the build output:
    report.csv

Comparing ./master_artifact/chip-standalone-demo.out and ./pull_artifact/chip-standalone-demo.out:

sections,vmsize,filesize

[github-actions]

Size increase report for "esp32-example-build"

File	Section	File	VM

Full report output

BLOAT REPORT

Files found only in the build output:
    report.csv

Comparing ./master_artifact/chip-wifi-echo.elf and ./pull_artifact/chip-wifi-echo.elf:

sections,vmsize,filesize

[github-actions]

Size increase report for "gn_nrf-example-build"

File	Section	File	VM

Full report output

BLOAT REPORT

Files found only in the build output:
    report.csv

[github-actions]

Size increase report for "gn_linux-example-build"

File	Section	File	VM

Full report output

BLOAT REPORT

Files found only in the build output:
    report.csv