boards: arm: silabs_exx32: correct Kconfig option prompt

Fix a typo in the option prompt for Kconfig symbol
SOC_SERIES_EFM32GG11B.

Signed-off-by: Ioannis Glaropoulos <[email protected]>

Author: ioannisg

soc/arm/silabs_exx32/efm32gg11b/Kconfig.series

@@ -4,7 +4,7 @@
 # SPDX-License-Identifier: Apache-2.0
 
 config SOC_SERIES_EFM32GG11B
-	bool "EFM32PG11B Series MCU"
+	bool "EFM32GG11B Series MCU"
 	select ARM
 	select HAS_SILABS_GECKO
 	select HAS_SWO