cc13xx and cc26xx serial boards i2c scan not work

[Pillar1989]

Describe the bug
I believe that's a common issue. because i2c scan function is merged recently.
#21797

To Reproduce
Steps to reproduce the behavior:

1. mkdir build; cd build
2. cmake -DBOARD=cc1352r1_launchxl
3. make
4. See error

Expected behavior
i2c can work like this.

uart:~$ i2c scan I2C_2
     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
00:             -- -- -- -- -- -- -- -- -- -- -- --
10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- 1e --
20: -- -- -- -- -- -- -- -- -- 29 -- -- -- 2d -- --
30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
50: -- -- -- -- -- -- 56 -- -- -- -- -- -- 5d -- 5f
60: -- -- -- -- -- -- -- -- -- -- 6a -- -- -- -- --
70: -- -- -- -- -- -- -- --
7 devices found on I2C_2

Impact
The impact is minor, it's just not functional.

Logs and console output
No such logs

Environment (please complete the following information):
common issue, so ignore the environment

Additional context
nothing

[cfriedt]

As discussed in the linked PR, this SoC is not capable of transmitting the address without any data byte, and therefore scanning was previously disabled.

One possible solution may involve the upcoming pinctrl feature.

Essentially the i2c pin configuration would be swapped out for GPIO pin configuration at runtime for a scan operation.

The cc13xx_cc26xx i2c driver would then instruct the GPIO I2C driver to bit-bang the address and analyze whether a NAK or ACK was received for the address word. When scanning is finished, the original pin configuration (i2c hw) would be restored.

Note, Zephyr already has a GPIO I2C driver, so the cc13xx_cc26xx driver would need to have a phandle to the GPIO i2c device.

This solution could be used for any SoC with buggy i2c hardware, as long as the SoC supported pinctrl / runtime pin reconfiguration.

Other pinctrl-specific calls may be required.

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