If the only GYN care you need is a Pap and your PCP is comfortable and competent doing the test then using the PCP is entirely reasonable. However, you also should review the updated recommendations on how often you need to have one done. The frequency depends on your age, number of normal previous tests and other factors. For some women the recommended frequency is never.
Pap Smear After Menopause: How Often to Get a Pap Smear and More