Makefile: No need to mkdir when distclean

make distclean causes error on mingw:
-------
rm: cannot lstat `build/util': Permission denied
make: *** [distclean] Error 1
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Guess, When the distclean is made by multi-process, the mkdir
in the Makefile will execute when build is removed. That causes
conflicts.

Change-Id: Ia41ecc5d1db2fa9d3328c81ac1d33fa94779492d
Signed-off-by: Zheng Bao <zheng.bao@amd.com>
Signed-off-by: Zheng Bao <fishbaozi@gmail.com>
Reviewed-on: http://review.coreboot.org/1602
Tested-by: build bot (Jenkins)
Reviewed-by: Patrick Georgi <patrick@georgi-clan.de>
1 file changed