Remove -j ${NJOBS} from make invocations in the ci

According to
https://www.gnu.org/software/make/manual/html_node/Options_002fRecursion.html#Options_002fRecursion
it's not necessary, because we pass `-j ${NJOBS}` to the top-level `make`
invocation in `.travis.yml`.  Additionally, explicitly passing `-j` in,
e.g., fiat-crypto, results in error messages such as
```
make[2]: *** write jobserver: Bad file descriptor.  Stop.
make[2]: *** Waiting for unfinished jobs....
make[2]: *** write jobserver: Bad file descriptor.  Stop.
make[1]: *** [coqprime] Error 2
make[1]: INTERNAL: Exiting with 1 jobserver tokens available; should be 2!
make[1]: Leaving directory `/home/travis/build/JasonGross/coq/_build_ci/fiat-c
```
because the `-j` on the `make` in the `ci-fiat-crypto.sh` script
disables jobserver mode, and the submake in fiat-crypto to make coqprime
does not explicitly pass `-j`, and so reenables jobserver mode, and then
`make` gets very confused.

Commit made with
```bash
cd dev/ci
git grep --name-only -- 'make -j ${NJOBS}' | xargs sed s'/make -j \${NJOBS}/make/g' -i
 git grep --name-only -- 'make -f Makefile.coq -j ${NJOBS}' | xargs sed s'/make -f Makefile.coq -j \${NJOBS}/make -f Makefile.coq/g' -i
```

1 files changed, 1 insertions, 1 deletions

diff --git a/dev/ci/ci-hott.sh b/dev/ci/ci-hott.sh
index 1bf6e9a87..693135a4c 100755
--- a/dev/ci/ci-hott.sh
+++ b/dev/ci/ci-hott.sh
@@ -7,4 +7,4 @@ HoTT_CI_DIR=${CI_BUILD_DIR}/HoTT
 
 git_checkout ${HoTT_CI_BRANCH} ${HoTT_CI_GITURL} ${HoTT_CI_DIR}
 
-( cd ${HoTT_CI_DIR} && ./autogen.sh && ./configure && make -j ${NJOBS} )
+( cd ${HoTT_CI_DIR} && ./autogen.sh && ./configure && make )