package/libmodsecurity: drop AC_CHECK_FILE workaround

Drop AC_CHECK_FILE workaround as it is not needed since version 3.0.4:
https://github.com/SpiderLabs/ModSecurity/commit/8af8cad90779a64af87d29b3a44f3ea2e0a270c2

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

package/libmodsecurity/libmodsecurity.mk

@@ -14,9 +14,6 @@ LIBMODSECURITY_CPE_ID_VENDOR = trustwave
 LIBMODSECURITY_CPE_ID_PRODUCT = modsecurity
 # 0002-test-for-uClinux-in-configure-script.patch
 LIBMODSECURITY_AUTORECONF = YES
-# libinjection uses AC_CHECK_FILE, not available in cross-compile
-LIBMODSECURITY_CONF_ENV = \
-	ac_cv_file_others_libinjection_src_libinjection_html5_c=yes
 
 LIBMODSECURITY_DEPENDENCIES = pcre
 LIBMODSECURITY_CONF_OPTS = \