Fix up typos

Ran automated checker for common typos [1]. Most of these changes have
no functional change *except* for `./ci/sim_run.sh` where, previously
the `bootstrap` feature wasn't being selected properly.

I didn't touch anything in the `./ext/` folder as anything in there
should probably be fixed in the upstream repo.

[1] https://github.com/codespell-project/codespell

Signed-off-by: Sam Bristow <sam@bristow.nz>
diff --git a/ci/sim_run.sh b/ci/sim_run.sh
index b0b70f7..3a9b0df 100755
--- a/ci/sim_run.sh
+++ b/ci/sim_run.sh
@@ -17,7 +17,7 @@
 EXIT_CODE=0
 
 if [[ ! -z $SINGLE_FEATURES ]]; then
-  all_features="sig-rsa sig-ecdsa overwrite-only validate-primary-slot enc-rsa enc-kw boostrap"
+  all_features="sig-rsa sig-ecdsa overwrite-only validate-primary-slot enc-rsa enc-kw bootstrap"
 
   if [[ $SINGLE_FEATURES =~ "none" ]]; then
     echo "Running cargo with no features"