ARM: configs: at91: sama7: enable cpu idle

Enable CPU idle support for SAMA7 config.
Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Link: https://lore.kernel.org/r/20220113144900.906370-10-claudiu.beznea@microchip.com

arch/arm/configs/sama7_defconfig

@@ -26,6 +26,7 @@ CONFIG_FORCE_MAX_ZONEORDER=15
 CONFIG_UACCESS_WITH_MEMCPY=y
 # CONFIG_ATAGS is not set
 CONFIG_CMDLINE="console=ttyS0,115200 earlyprintk ignore_loglevel"
+CONFIG_CPU_IDLE=y
 CONFIG_VFP=y
 CONFIG_NEON=y
 CONFIG_KERNEL_MODE_NEON=y