First, I don't think the blocks resemble swastikas. They're missing that outer leg on all four sides. To me, it just looks like some kind of spinning block.
Second, it's too bad that anytime one looks at such a symbol, all we see is the negative connotation of Hitler. Until the Nazis used this symbol, the swastika was used by many cultures throughout the past 3,000 years to represent life, sun, power, strength, and good luck.
I hope your mom likes it as is. As others have stated, I'm not sure how you could change it without completely remaking the entire quilt.