utils: dec2bcd8: Make calculation reflect bcd2dec8 in implementation

This is purely a visual improvement to help correlate the implementation
with bcd2dec8().

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Change-Id: I7c4fb3e3191e4b198181b4d99da75d89bb4cd139
diff --git a/src/utils.c b/src/utils.c
index d1a000c..b4b930b 100644
--- a/src/utils.c
+++ b/src/utils.c
@@ -151,7 +151,7 @@
 
 uint8_t dec2bcd8(uint8_t dec)
 {
-	return (dec % 10) | (dec / 10) << 4;
+	return ((dec / 10) << 4) + (dec % 10);
 }
 
 uint16_t bcd2dec16(uint16_t bcd)