Tools: multiple region - tools error msg improvement

[0xc0170]

Description

• Type: Enhancement
• Related issue: ARMCC - FromELF multiple regions #5021
• Priority: Minor

Referenced PR above , there is this request:

The problem

ELF files containing multiple regions were being converted to a folder with each region as a separate file, this caused the build scripts to fail since the .bin was not created.

Possibly enhancement

Maybe the mbed-os build tools should print a nicely formatted error message if this occurs and there isn't a post build hook for the platform

@theotherjimmy Please add more information if needed

cc @chrissnow

[theotherjimmy]

@0xc0170 That looks correct. I changed the related issue field so that it links correctly.

[ciarmcom]

ARM Internal Ref: MBOTRIAGE-126

[cmonr]

Closing this since referred PR has since been closed.