scripts/functions: extract: portable call for old and defective tars

Instead of using -J, --lzma, --use-compress-program or the like
use <compressor> -dc <file> | tar -f -

Signed-off-by: Titus von Boxberg <titus@v9g.de>

# Alpha specific configuration file

## select ARCH_SUPPORTS_32

## select ARCH_DEFAULT_32

## select ARCH_USE_MMU

## select ARCH_SUPPORT_CPU

## select ARCH_SUPPORT_TUNE

##

## help The Alpha architecture.