ARM: Scorpion is a v7 architecture, not v6

Scorpion processors have always been v7 CPUs. Fix the Kconfig
text to reflect this.

Reported-by: Stepan Moskovchenko <stepanm@codeaurora.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>