[iMXRT700] Rename the GPIO peripheral to RGPIO so that it matches the naming scheme of the iMXRT1180

[Masmiseim36]

Prerequisites

• I have checked latest main branch and the issue still exists.
• I did not see it is stated as known-issue in release notes.
• No similar GitHub issue is related to this change.
• My code follows the commit guidelines of this project.
• I have performed a self-review of my own code.
• My changes generate no new warnings.
• I have added tests that prove my fix is effective or that my feature works.

Describe the pull request
Rename the GPIO peripheral to RGPIO so that it matches the naming scheme of the iMXRT1180. The same IP should be named identically so that it can be addressed by the same driver.

Type of change

• Breaking change (fix or feature that would cause existing functionality to not work as expected)
  May break sw which uses the peripheral names of the current version. But simplifies using the existing driver for the RGMI-Peripheral

Tests

Still open. The current releases for the iMXRT700 family are still somewhat incomplete and examples are missing