Environment:
Windows Server 2016 + VS2017 + openssl master branch latest source code.

Issue description:
I tried to build openssl using VS2017 on Windows Server 2016. We found that openssl failed to nmake clean due to fatal error U1095: expanded command line 'rmdir /Q /S doc\html\man3\ADMISSIONS.html on windows with MSVC. It can be reproduced on latest master revision be3acd7 reversion. Could you please help take a look at this? Thanks in advance!

Repro steps:

1. git clone https://github.com/openssl/openssl D:\openssl\src
2. cd D:\openssl\src
3. perl Configure VC-WIN32
4. nmake clean

log_x86_build_1.log

Actual result:
NMAKE : fatal error U1095: expanded command line 'rmdir /Q /S doc\html\man3\ADMISSIONS.html