[BUG] Error while trying to git apply a patch; works with patch -p1

[Eneas Queiroz <cotequeiroz@gmail.com>]

I've sent this to the list 2 days ago, but I can't find it in the list
archives, so I'm sending it again without files attached.  I apologize
if this is a duplicate. One should be able to reproduce this with the
current PR files, but if not, I can provide them.

I've hit a strange error while trying to apply a patch from github
here: https://github.com/openwrt/openwrt/pull/965

965.patch:452: trailing whitespace.

965.patch:559: space before tab in indent.
             -o $(SHLIBNAME_FULL) \
965.patch:560: space before tab in indent.
             $$ALLSYMSFLAGS $$SHOBJECTS $$NOALLSYMSFLAGS $$LIBDEPS; \
965.patch:564: space before tab in indent.
        -o $(SHLIBNAME_FULL) \
965.patch:2334: trailing whitespace.

error: package/libs/openssl/patches/100-Configure-afalg-support.patch:
No such file or directory
error: package/libs/openssl/patches/110-openwrt_targets.patch: No such
file or directory
error: package/libs/openssl/patches/120-fix_link_segfault.patch: No
such file or directory
error: package/libs/openssl/patches/1.1.0/100-Configure-afalg-support.patch:
No such file or directory
error: package/libs/openssl/patches/1.1.0/110-openwrt_targets.patch:
No such file or directory

If you get the patch file from
https://github.com/openwrt/openwrt/pull/965.patch and apply it with
git apply, it fails.  If I apply the same file with patch -p1, it
works fine.  I've tried it with git 2.16.4 and 2.19, and they both
fail with the same error, and at least 2 more people have confirmed
it.

git apply fails even when using git format-patch -13 --stdout as a
source, so it is not github doing something weird.

The file is a series of 13 patches.  If I split the series after the
3rd patch, it works.
Also, if I use https://github.com/openwrt/openwrt/pull/965.diff, it also works.

I'm not subscribed to the list, so please CC me.

Cheers,

Eneas