memory: move jedec_ddr_data.c from lib/ to drivers/memory/

jedec_ddr_data.c exports 3 symbols, and all of them are only
referenced from drivers/memory/{emif.c,of_memory.c}

drivers/memory/ is a better location than lib/.

I removed the Kconfig prompt "JEDEC DDR data" because it is only
select'ed by TI_EMIF, and there is no other user. There is no good
reason in making it a user-configurable CONFIG option.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Olof Johansson <olof@lixom.net>