menu: remove CTRL+C to quit

On the sandbox called without "--terminal raw" CTRL+C leaves U-Boot,
"ESC/CTRL+C to quit" is misleading.

Let's remove CTRL+C to quit key handling from bootmenu and eficonfig menu.

Signed-off-by: Masahisa Kojima <masahisa.kojima@linaro.org>
Reviewed-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
diff --git a/cmd/eficonfig.c b/cmd/eficonfig.c
index 47c04cf..f365a98 100644
--- a/cmd/eficonfig.c
+++ b/cmd/eficonfig.c
@@ -23,12 +23,12 @@
 
 static struct efi_simple_text_input_protocol *cin;
 const char *eficonfig_menu_desc =
-	"  Press UP/DOWN to move, ENTER to select, ESC/CTRL+C to quit";
+	"  Press UP/DOWN to move, ENTER to select, ESC to quit";
 
 static const char *eficonfig_change_boot_order_desc =
 	"  Press UP/DOWN to move, +/- to change orde\n"
 	"  Press SPACE to activate or deactivate the entry\n"
-	"  Select [Save] to complete, ESC/CTRL+C to quit";
+	"  Select [Save] to complete, ESC to quit";
 
 static struct efi_simple_text_output_protocol *cout;
 static int avail_row;
@@ -927,7 +927,7 @@
 	       ANSI_CURSOR_POSITION
 	       "%s"
 	       ANSI_CURSOR_POSITION
-	       "  Press ENTER to complete, ESC/CTRL+C to quit",
+	       "  Press ENTER to complete, ESC to quit",
 	       0, 1, msg, 8, 1);
 
 	/* tmp is used to accept user cancel */