ARM: mach-s3c24a0: delete

Commit bcae8aeb "[ARM] S3C24A0: Initial architecture support files"
brought in a bunch of files while explicitly leaving out the corresponding
Kconfig entry, stating that the series is not complete.

More than 2.5 years later, the support for this has not seen any progress.
This is therefore dead code.  If someone wants to revive this code, it is
always possible to retrieve it from the Git repository.

Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Acked-by: Ben Dooks <ben-linux@fluff.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>