format code according to conventions [skip ci]

tmk_core/common/chibios/printf.c

@@ -98,8 +98,8 @@ static int a2d(char ch) {
 
 static char a2i(char ch, const char** src, int base, int* nump) {
     const char* p   = *src;
-    int   num = 0;
-    int   digit;
+    int         num = 0;
+    int         digit;
     while ((digit = a2d(ch)) >= 0) {
         if (digit > base) break;
         num = num * base + digit;