[PATCH] m68k: lib: Include <linux/libgcc.h> for __muldi3()

[Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>]

When building with W=1:

    arch/m68k/lib/muldi3.c:82:1: warning: no previous prototype for ‘__muldi3’ [-Wmissing-prototypes]
       82 | __muldi3 (DItype u, DItype v)
	  | ^~~~~~~~

Fix this by including <linux/libgcc.h>.

Signed-off-by: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
---
To bequeued in the m68k for-v6.7 branch.

Missed before, as "make arch/m68k/" does not (re)build arch/m68k/lib/?

arch/m68k/Makefile has:

    libs-y += arch/m68k/lib/

while all the other subdirs use "obj-y".
---
 arch/m68k/lib/muldi3.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/m68k/lib/muldi3.c b/arch/m68k/lib/muldi3.c
index eb7d9d86ff6697a5..5012a9b218c7824c 100644
--- a/arch/m68k/lib/muldi3.c
+++ b/arch/m68k/lib/muldi3.c
@@ -16,6 +16,7 @@ GNU General Public License for more details. */
 
 #include <linux/compiler.h>
 #include <linux/export.h>
+#include <linux/libgcc.h>
 
 #ifdef CONFIG_CPU_HAS_NO_MULDIV64
 
-- 
2.34.1