leds: simatic-ipc-leds: Add missing MODULE_DESCRIPTION() macros

Fix the 'make W=1' issues:

WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/leds/simple/simatic-ipc-leds-gpio-apollolake.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/leds/simple/simatic-ipc-leds-gpio-core.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/leds/simple/simatic-ipc-leds-gpio-elkhartlake.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/leds/simple/simatic-ipc-leds-gpio-f7188x.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/leds/simple/simatic-ipc-leds.o

Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Link: https://lore.kernel.org/r/20240517-md-simatic-ipc-v1-1-bbbd199262b8@quicinc.com


Signed-off-by: Lee Jones <lee@kernel.org>