block: m25p80: Improve 1GiB Micron flash definition

n25q00 and mt25q01 devices share the same JEDEC ID. The difference
between those two devices is number of dies and one bit in extended
JEDEC bytes. This commit adds proper entry for both devices by
introduction the number of dies and and new 25q00 entries.

Signed-off-by: Marcin Krzeminski <mar.krzeminski@gmail.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Message-id: 20170108083854.5006-4-mar.krzeminski@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>