lmb: remove __maybe_unused from lmb_map_update_notify

Function lmb_map_update_notify() is always referenced.

Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
diff --git a/lib/lmb.c b/lib/lmb.c
index 96a055f..2ed0da2 100644
--- a/lib/lmb.c
+++ b/lib/lmb.c
@@ -35,9 +35,8 @@
 		CONFIG_IS_ENABLED(EFI_LOADER);
 }
 
-static int __maybe_unused lmb_map_update_notify(phys_addr_t addr,
-						phys_size_t size,
-						u8 op, enum lmb_flags flags)
+static int lmb_map_update_notify(phys_addr_t addr, phys_size_t size, u8 op,
+				 enum lmb_flags flags)
 {
 	u64 efi_addr;
 	u64 pages;