configs: sama5d4_xplained: Fix input clock for debug UART

Fix the UART input clock for the early debug UART, it should be
100MHz, instead of 88MHz.

Signed-off-by: Wenyou Yang <wenyou.yang@microchip.com>
diff --git a/configs/sama5d4_xplained_mmc_defconfig b/configs/sama5d4_xplained_mmc_defconfig
index 6527733..8fa2e25 100644
--- a/configs/sama5d4_xplained_mmc_defconfig
+++ b/configs/sama5d4_xplained_mmc_defconfig
@@ -58,7 +58,7 @@
 CONFIG_DM_SERIAL=y
 CONFIG_DEBUG_UART_ATMEL=y
 CONFIG_DEBUG_UART_BASE=0xfc00c000
-CONFIG_DEBUG_UART_CLOCK=88000000
+CONFIG_DEBUG_UART_CLOCK=100000000
 CONFIG_DEBUG_UART_BOARD_INIT=y
 CONFIG_DEBUG_UART_ANNOUNCE=y
 CONFIG_ATMEL_USART=y