[PATCH] coredump: Fix build error for ‘dump_emit_page’ defined but not used

[Li Hua <hucool.lihua@xxxxxxxxxx>]

If CONFIG_ELF_CORE is not set:
    fs/coredump.c:834:12: error: ‘dump_emit_page’ defined but not used [-Werror=unused-function]
    static int dump_emit_page(struct coredump_params *cprm, struct page *page)
            ^~~~~~~~~~~~~~

Fix this by adding the missing CONFIG_ELF_CORE for dump_emit_page.

Fixes: 06bbaa6dc53c ("[coredump] don't use __kernel_write() on kmap_local_page()")
Signed-off-by: Li Hua <hucool.lihua@xxxxxxxxxx>
---
 fs/coredump.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/fs/coredump.c b/fs/coredump.c
index 7bad7785e8e6..8663042ebe9c 100644
--- a/fs/coredump.c
+++ b/fs/coredump.c
@@ -831,6 +831,7 @@ static int __dump_skip(struct coredump_params *cprm, size_t nr)
 	}
 }
 
+#ifdef CONFIG_ELF_CORE
 static int dump_emit_page(struct coredump_params *cprm, struct page *page)
 {
 	struct bio_vec bvec = {
@@ -863,6 +864,7 @@ static int dump_emit_page(struct coredump_params *cprm, struct page *page)
 
 	return 1;
 }
+#endif
 
 int dump_emit(struct coredump_params *cprm, const void *addr, int nr)
 {
-- 
2.17.1