Every time someone summons up the nerve to ask, “What’s wrong with the Spurs?” the defending NBA champions have provided an emphatic response: Nothing. They did it in November, beating the Clippers and Warriors on the road on consecutive nights after losses to Houston and New Orleans. They did it again in December, beating the Clippers to end a four-game losing streak that included back-to-back excruciating triple-overtime losses. And they did it again last night, beating the Rockets for the first time