powerpc: lib: remove leftover CONFIG_5xx

CONFIG_5xx hasn't existed since commit 502589777416 (powerpc, 5xx:
remove support for 5xx). Remove this last mention of it.

Reviewed-by: Stefan Roese <sr@denx.de>
Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
1 file changed