The shmlba.h file related to the LoongArch architecture was introduced
in commit 3eed5f3a1ee to address the mismatch in the SHMLBA definition
between glibc and the kernel.
Signed-off-by: Peng Fan <fanpeng@loongson.cn>
(cherry picked from commit 3b53810c70dfea943576a3f2774d62275bb2a851)