cmd/bdinfo: correct comment in board_detail

This appears to be a simple typo that dates back to the original
implementation of board_detail in commit e79394643b26 ("common: Update
cmd_bdinfo for PPC").

Signed-off-by: Chris Packham <judge.packham@gmail.com>
diff --git a/cmd/bdinfo.c b/cmd/bdinfo.c
index 81ac78d..96d7b72 100644
--- a/cmd/bdinfo.c
+++ b/cmd/bdinfo.c
@@ -166,7 +166,7 @@
 #if defined(CONFIG_PPC)
 void __weak board_detail(void)
 {
-	/* Please define boot_detail() for your platform */
+	/* Please define board_detail() for your platform */
 }
 
 int do_bdinfo(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])