LibCrypto: Remove some now-unused (and incorrect) methods

Removes the UnsignedBigInteger overloads of
SignedBigInteger::binary_{and,or,xor}(). They're now unused, and they
also didn't work when *this was negative.

Userland/Libraries/LibCrypto/BigInt/SignedBigInteger.cpp

@@ -143,21 +143,6 @@ FLATTEN SignedBigInteger SignedBigInteger::minus(const UnsignedBigInteger& other
     return { other.minus(m_unsigned_data), true };
 }
 
-FLATTEN SignedBigInteger SignedBigInteger::bitwise_or(const UnsignedBigInteger& other) const
-{
-    return { unsigned_value().bitwise_or(other), m_sign };
-}
-
-FLATTEN SignedBigInteger SignedBigInteger::bitwise_and(const UnsignedBigInteger& other) const
-{
-    return { unsigned_value().bitwise_and(other), false };
-}
-
-FLATTEN SignedBigInteger SignedBigInteger::bitwise_xor(const UnsignedBigInteger& other) const
-{
-    return { unsigned_value().bitwise_xor(other), m_sign };
-}
-
 FLATTEN SignedBigInteger SignedBigInteger::bitwise_not() const
 {
     // Bitwise operators assume two's complement, while SignedBigInteger uses sign-magnitude.

Userland/Libraries/LibCrypto/BigInt/SignedBigInteger.h

@@ -109,9 +109,6 @@ public:
 
     SignedBigInteger plus(const UnsignedBigInteger& other) const;
     SignedBigInteger minus(const UnsignedBigInteger& other) const;
-    SignedBigInteger bitwise_or(const UnsignedBigInteger& other) const;
-    SignedBigInteger bitwise_and(const UnsignedBigInteger& other) const;
-    SignedBigInteger bitwise_xor(const UnsignedBigInteger& other) const;
     SignedBigInteger multiplied_by(const UnsignedBigInteger& other) const;
     SignedDivisionResult divided_by(const UnsignedBigInteger& divisor) const;