[PATCH v2] um: Makefile: use bash from the environment

[Johannes Berg]

On Sat, 2024-03-23 at 17:44 +0000, Yueh-Shun Li wrote:
> Set Makefile SHELL to bash instead of /bin/bash for better portability.
> 
> Some systems do not install binaries to /bin, and therefore do not
> provide /bin/bash. This includes Linux distros which intentionally avoid
> implementing the Filesystem Hierarchy Standard (FHS), such as NixOS and
> Guix System.
> 
> The recipies inside arch/um/Makefile don't require top-level Bash to
> build, and setting "SHELL" to "bash" makes Make pick the Bash executable
> from the environment, hence this patch.
> 
> Changes since last roll:
> - Rebase onto a more recent commit on the master branch.
> - Remove a dangling in-text citation from the change log.
> - Reword the change log.

Not sure I'd have added the change log here (in this case at least), but
anyway:

Reviewed-by: Johannes Berg <johannes at sipsolutions.net

johannes