Fix for the validation of the bits located in the least signficant

bits of mem_section.section_mem_map pointers.  Without the patch,
the validation functions always returned valid, due to a coding
error found by clang.  However, it was never really a problem
because it is extremely unlikely that an existing mem_section would
ever be invalid.
(oleksandr@redhat.com, anderson@redhat.com)

memory.c

@@ -17003,20 +17003,26 @@ valid_section(ulong addr)
 
 	if ((mem_section = read_mem_section(addr)))
         	return (ULONG(mem_section + 
-			OFFSET(mem_section_section_mem_map)) && 
-			SECTION_MARKED_PRESENT);
+			OFFSET(mem_section_section_mem_map))
+			& SECTION_MARKED_PRESENT);
 	return 0;
 }
 
 int 
 section_has_mem_map(ulong addr)
 {
 	char *mem_section;
+	ulong kernel_version_bit;
+
+	if (THIS_KERNEL_VERSION >= LINUX(2,6,24))
+		kernel_version_bit = SECTION_HAS_MEM_MAP;
+	else
+		kernel_version_bit = SECTION_MARKED_PRESENT;
 
 	if ((mem_section = read_mem_section(addr)))
 		return (ULONG(mem_section + 
 			OFFSET(mem_section_section_mem_map))
-			&& SECTION_HAS_MEM_MAP);
+			& kernel_version_bit);
 	return 0;
 }