usb: pci-quirks: Reduce the length of a spinlock section in usb_amd_find_chipset_info()

'info' is local to the function. There is no need to zeroing it within
a spin_lock section. Moreover, there is no need to explicitly initialize
the .need_pll_quirk field.

Initialize the structure when defined and remove the now useless memset().

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/08ee42fced6af6bd56892cd14f2464380ab071fa.1679600396.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>