fatfs: Revert "Update error code mapping"

[geky]

Description

Reverts #6120

This pr was a part of work spanning 5.7-5.9. There is not an immediate urgency for it to land on 5.8. During the review process of the 5.8 release it was noted that this change may cause problems for users that are relying on the existing (but broken) error codes.

To minimize noise, the plan is to revert the error code changes until 5.9, where it can land along with proper testing and documentation from related filesystem work.

I'll recreate #6120 targeting 5.9 if this revert makes it into 5.8.

cc @kegilbert, @deepikabhavnani, @adbridge, @sg-, @kjbracey-arm, @JanneKiiskila

Pull request type

• Fix
• Refactor
• New target
• Feature
• Breaking change

[studavekar]

/morph build

[mbed-ci]

Build : SUCCESS

Build number : 1407
Build artifacts/logs : http://mbed-os.s3-website-eu-west-1.amazonaws.com/?prefix=builds/6323/

Triggering tests

/morph test
/morph uvisor-test
/morph export-build
/morph mbed2-build

[mbed-ci]

Exporter Build : SUCCESS

Build number : 1060
Build artifacts/logs : http://mbed-os.s3-website-eu-west-1.amazonaws.com/?prefix=builds/exporter/6323/

[mbed-ci]

Test : SUCCESS

Build number : 1194
Test logs :http://mbed-os-logs.s3-website-us-west-1.amazonaws.com/?prefix=logs/6323/1194