Avoid comparing 'max' with 'max\n'.

Fixes https://pagure.io/freeipa/issue/8764.

Reviewed-By: Rob Crittenden <rcritten@redhat.com>

ipaserver/install/installutils.py

@@ -1098,7 +1098,7 @@ def check_available_memory(ca=False):
             )
 
         with open(limit_file) as fd:
-            limit = fd.readline()
+            limit = fd.readline().rstrip()
         with open(usage_file) as fd:
             used = int(fd.readline())