CVE-2025-21949 LoongArch: Set hugetlb mmap base address aligned with pmd size

In the Linux kernel, the following vulnerability has been resolved: LoongArch: Set hugetlb mmap base address aligned with pmd size With ltp test case "testcases/bin/hugefork02", there is a dmesg error report message such as: kernel BUG at mm/hugetlb.c:5550! Oops - BUG1: CPU: 0 UID: 0 PID: 1517...