global: Use proper project name U-Boot (next)

Use proper project name in DTs, messages and READMEs.

Signed-off-by: Michal Simek <michal.simek@amd.com>
diff --git a/board/imgtec/boston/checkboard.c b/board/imgtec/boston/checkboard.c
index 1b8a47d..c246a7b 100644
--- a/board/imgtec/boston/checkboard.c
+++ b/board/imgtec/boston/checkboard.c
@@ -16,7 +16,7 @@
 {
 	u32 changelist;
 
-	lowlevel_display("U-boot  ");
+	lowlevel_display("U-Boot  ");
 
 	printf("Board: MIPS Boston\n");