gitignore: Add MIPS vmlinux.32 to the list

MIPS64 kernels builds will produce a vmlinux.32 kernel image for
compatibility, ignore them.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
diff --git a/.gitignore b/.gitignore
index 4ad4a98..34d6bad 100644
--- a/.gitignore
+++ b/.gitignore
@@ -44,6 +44,7 @@
 /TAGS
 /linux
 /vmlinux
+/vmlinux.32
 /vmlinux-gdb.py
 /vmlinuz
 /System.map