[_dq_quadprog_solver.py] Fixing typo in b.

Author: mmmarinho

dqrobotics/solvers/_dq_quadprog_solver.py

@@ -64,7 +64,7 @@ def solve_quadratic_program(self, H, f, A, b, Aeq, beq):
         """
         A_internal = A if A is not None else Aeq
         b_internal = b if b is not None else beq
-        if A is not None and B is not None and Aeq is not None and beq is not None:
+        if A is not None and b is not None and Aeq is not None and beq is not None:
             if Aeq.shape == (0, 0) or beq.shape == 0:
                 pass
             else: