refactor: avoid using the elf module for performance reasons

yara/virus/Linux.Virus.Vit.yara

@@ -1,5 +1,3 @@
-import "elf"
-
 rule Linux_Virus_Vit : tc_detection malicious
 {
     meta:
@@ -32,5 +30,5 @@ rule Linux_Virus_Vit : tc_detection malicious
       $vit_str = "vi324.tmp"
 
     condition:
-        uint32(0) == 0x464C457F and $vit_entry_point at elf.entry_point and $vit_str
-}
+        uint32(0) == 0x464C457F and all of them
+}