arm-toolchain: merge binary toolchain recipes

Merge the majority of the binary toolchain recipes for building on an
x86 host into a common include file.

Also, found and fixed an error with both install commands where the name
was double nested on the copy.  For example,
/usr/share/arm-none-eabi/arm-none-eabi/ due to the way it was being
copied.

Signed-off-by: Jon Mason <jdmason@kudzu.us>
Reviewed-by: Diego Sueiro <diego.sueiro@arm.com>