Avoid 'double assigments' tricks

Bitboard init code is already noteasy to follow,
so don't make it even harder using 'smart' code.

Also reindent a while loop in standard way.

No functional change.

src/bitboard.cpp

@@ -149,7 +149,10 @@ const std::string Bitboards::pretty(Bitboard b) {
 void Bitboards::init() {
 
   for (Square s = SQ_A1; s <= SQ_H8; ++s)
-      BSFTable[bsf_index(SquareBB[s] = 1ULL << s)] = s;
+  {
+      SquareBB[s] = 1ULL << s;
+      BSFTable[bsf_index(SquareBB[s])] = s;
+  }
 
   for (Bitboard b = 1; b < 256; ++b)
       MS1BTable[b] = more_than_one(b) ? MS1BTable[b - 1] : lsb(b);
@@ -301,7 +304,8 @@ namespace {
         // Find a magic for square 's' picking up an (almost) random number
         // until we find the one that passes the verification test.
         do {
-            do magics[s] = rk.magic_rand<Bitboard>(booster);
+            do
+                magics[s] = rk.magic_rand<Bitboard>(booster);
             while (popcount<Max15>((magics[s] * masks[s]) >> 56) < 6);
 
             std::memset(attacks[s], 0, size * sizeof(Bitboard));