fix: make format after updating gn

update formatting after updating gn tool [1]

[1] https://review.trustedfirmware.org/c/hafnium/hafnium/+/19180

Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
Change-Id: Ib9250c3cd71faafb3c58cde591275048a660e973
diff --git a/rpi/BUILD.gn b/rpi/BUILD.gn
index c6e03cf..3bd9a33 100644
--- a/rpi/BUILD.gn
+++ b/rpi/BUILD.gn
@@ -7,9 +7,7 @@
 import("args.gni")
 
 source_set("mini_uart") {
-  sources = [
-    "mini_uart.c",
-  ]
+  sources = [ "mini_uart.c" ]
 
   assert(gpio_base_address != 0,
          "\"gpio_base_address\" must be defined for ${target_name}.")