ver_linux: complete awk implementation

The algorithm that extracts the version number of the utility being
queried, and prints the name of the utility and its version number is
currently implemented in awk. The code is used throughout the script,
making its use repetative. The proposed implementation confines the
algorithm in question to a function, which makes the script easier to
read overall, as well as considerably reduces the number of lines of
code. Every attempt has been made to retain the look and the format
generated by the current implementation.

Signed-off-by: Alexander Kapshuk <alexander.kapshuk@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>