Power Management: Add LPM Documentation for J7200 and J784S4

[PrasanthBabuMantena]

J7200 and J784S4 supports two low poer modes, SOC_OFF and IO_ONLY_PLUS_DDR. Add related documentation for the modes supported and their usage details.

[github-actions]

New warnings found with rstcheck:

source/linux/Foundational_Components/Power_Management/pm_low_power_modes_socoff.rst:59: (WARNING/2) Title overline too short.
source/linux/Foundational_Components/Power_Management/pm_low_power_modes_socoff.rst:59: (WARNING/2) Title overline too short.

[uditkumarti]

New warnings found with rstcheck:

source/linux/Foundational_Components/Power_Management/pm_low_power_modes_socoff.rst:59: (WARNING/2) Title overline too short.
source/linux/Foundational_Components/Power_Management/pm_low_power_modes_socoff.rst:59: (WARNING/2) Title overline too short.

@PrasanthBabuMantena Please take care of bot warnings

[cshilwant]

there are few warnings reported by vale which needs to be addressed
checkout https://github.com/TexasInstruments/processor-sdk-doc/pull/566/files

[uditkumarti]

$subject should start with feat or something,
Please do git log to see format

[github-actions]

New warnings found with rstcheck:

source/linux/Foundational_Components_Multimedia_wave5.rst:740: (INFO/1) Duplicate implicit target name: "example commands".
source/linux/Foundational_Components_Multimedia_wave5.rst:823: (ERROR/3) Error in "code-block" directive:
source/linux/Foundational_Components_Multimedia_wave5.rst:835: (ERROR/3) Error in "code-block" directive:

[StaticRocket]

Also some vale warnings about passive voice

[StaticRocket]

@StaticRocket @cshilwant , only one vale error is that it asks to expand DDR to Double data* in the first reference. Is it required really ?

Nah, I've been fairly lax on acronyms unless they are domain specific. It's the passive voice and simplified language I'm more concerned about. There are still warnings about passive voice.

[kwillis01]

I think it could be good to add a comparison table of SoC off and I/O Only + DDR LPMs so that customers can easily see the differences. Table could include which has better power consumption, resume latency, how it resumes, etc.

[PrasanthBabuMantena]

@StaticRocket All the passive to active voice conversions have been made and I dont see any warning on that pov now on vale.

[PrasanthBabuMantena]

Please approve this PR if you don't have any further comments.

[uditkumarti]

PR looks ok. Please address vale warning

[gehariprasath]

Thanks for addressing my comments