rpm: Remove /@unixroot/bin/sh dependency

[dmik]

It tuns out that many packages now depend on the /@unixroot/bin/sh file (i.e. have it among their requirements). This is a virtual dependency since this file doesn't even exist. Instead, it is virtually provided by the ash package.

Since it's a non-existent file, this dependency in the given form looks very strange. Perhaps it is a deviation of the common /bin/sh dependency found in many linux packages but this still doesn't make it sane. If we want a virtual dependency, it's better to stick with sh instead as it doesn't create any path confusion.

[dmik]

Yuri Dario says that this dependency is magically inserted by rpmbuild into each package that meets some conditions (perhaps into each packages where a shell script is found). However, I could not find this place. Perhaps it is hidden in C macros generated at build time.

[Yuri Dario]

This is coming from execution of /usr/lib/rpm/script.req against script files.
To avoid editing all scripts around (which is not really necessary), I'm going to add automatic remapping for /bin.

rpm: remap /bin to /@unixroot/usr/bin. fixes ticket#137.
Committed revision r636.