arm: juno: Fix UART clock rate

The UART base clock rate was typo-ed in the header file, probably because
the reference (the Linux .dts) was also wrong[1].

Fix the number to make the baud rate more correct.
Signed-off-by: NAndre Przywara <andre.przywara@arm.com>
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>

[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=39a1a8941b2Reviewed-by: NSimon Glass <sjg@chromium.org>

include/configs/vexpress_aemv8a.h

@@ -102,7 +102,7 @@
 
 /* PL011 Serial Configuration */
 #ifdef CONFIG_TARGET_VEXPRESS64_JUNO
-#define CONFIG_PL011_CLOCK		7273800
+#define CONFIG_PL011_CLOCK		7372800
 #else
 #define CONFIG_PL011_CLOCK		24000000
 #endif