erofs-utils: update .gitignore

Add more extensions to .gitignore.

Link: https://lore.kernel.org/r/20201202095345.10485-1-hsiangkao@aol.com
Reviewed-by: Li Guifu <bluce.lee@aliyun.com>
Signed-off-by: Gao Xiang <hsiangkao@aol.com>
diff --git a/.gitignore b/.gitignore
index 3a39a1e..8bdd505 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,11 +1,16 @@
 .*
 *~
+*.[ao]
 *.diff
-*.o
 *.la
-*.a
+*.lo
+*.mod.c
+*.orig
 *.patch
 *.rej
+*.so
+*.so.dbg
+*.tar.*
 
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