ANDROID: mm: Use intended order-adjusted batch size

Commit 44042b44 ("mm/page_alloc: allow high-order pages to be stored
on the per-cpu lists") adjusts the pcp batch size __rmqueue_pcplist()
allocates from rmqueue_bulk() in proportion to the page order.

This line was not properly carried forward when porting
commit 37b2d597 ("ANDROID: mm: add cma pcp list") to android 13-5.15.

Fixes: 37b2d597 ("ANDROID: mm: add cma pcp list")
Bug: 260129859
Change-Id: I28b7c22c75596176fd951974d1dd682ee1014efb
Signed-off-by: Patrick Daly <quic_pdaly@quicinc.com>
(cherry picked from commit 4931d96e)