Fix lazy init and prevent un-necessary calls to NativeInit

[sharmavishnu]

Stub changes due to change in I2C core library

Description

Everytime "I2cDevice.FromId" method is called, the "NativeInit" method gets called. This method should be called only once per I2C bus. This fix ensures that NativeInit is called only when a new I2C bus is used in managed code

Motivation and Context

1. Improve code
2. Another attempt to fix I2C hang issue as reported in ToString() causing hardfault Home#416 and Debugging SPI with single-stepping fails for second time onwards Home#424

How Has This Been Tested?

Tested with HTU21D I2C sensor. So far have been able to debug multiple times with no I2C hang.

Screenshots

Types of changes

• Improvement (non-breaking change that improves a feature, code or algorithm)
• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

Signed-off-by: @sharmavishnu

[nfbot]

Hi @sharmavishnu,

I'm nanoFramework bot.
Thank you for your contribution!

A human will be reviewing it shortly. 😉

[josesimoes]

@sharmavishnu could you please rebase your branch on "upstream/develop" so this PR isn't showing all these unrelated commits?

Remember to pull the changes first as I've just updated it with the latest changes from develop.

[josesimoes]

Almost forgot: please update the I2c assembly declaration on the FreeRTOS\ESP32 target.

[sharmavishnu]

1. I have rebased my fork with the upstream. I still see those older commit messages. Can you point me to the right reading material on the internet to fix this
2. I have pushed same changes to ESP32, but do not have a board with me to check.

[josesimoes]

@sharmavishnu you are submitting the PR from your develop branch. That causes all sorts of issues when updating from upstream.
Lacking a better (or detailed tutorial) suggest that you follow our contribution workflow.

Basically:

1. Leave develop branch alone and use it to update from upstream. This is you safety net in case you need to get back, revert or start a new branch.
2. Work from and submit PRs from features branches. You can isolate work, pull from upstream-develop, rebase and keep a clean history.

[josesimoes]

I'm opening a branch for this PR to fix the commits and remove the changes.txt file and merge from there.