Revert "heimdal: disable parallel make"

This reverts commit f6980126f26c63421d04a32b6710d9e3a380476a.

Parallel make was disabled back in 2017:
https://git.buildroot.net/buildroot/commit/?id=f6980126f26c63421d04a32b6710d9e3a380476a

Build-test with -j99 was successful.

Signed-off-by: Bernd Kuhls <bernd.kuhls@t-online.de>
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>

package/heimdal/heimdal.mk

@@ -8,7 +8,6 @@ HEIMDAL_VERSION = 7.7.0
 HEIMDAL_SITE = https://github.com/heimdal/heimdal/releases/download/heimdal-$(HEIMDAL_VERSION)
 HOST_HEIMDAL_DEPENDENCIES = host-e2fsprogs host-ncurses host-pkgconf
 HEIMDAL_INSTALL_STAGING = YES
-HEIMDAL_MAKE = $(MAKE1)
 # static because of -fPIC issues with e2fsprogs on x86_64 host
 HOST_HEIMDAL_CONF_OPTS = \
 	--disable-shared \