ftrace/recordmcount: Modify only executable sections

PROGBITS is not enough to determine if the section should be modified
or not. Only process sections that are marked as executable.

Cc: John Reiser <jreiser@bitwagon.com>
Link: http://lkml.kernel.org/r/20110421023737.991485123@goodmis.org
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

scripts/recordmcount.h

@@ -360,6 +360,7 @@ __has_rel_mcount(Elf_Shdr const *const relhdr,  /* is SHT_REL or SHT_RELA */
 		succeed_file();
 	}
 	if (w(txthdr->sh_type) != SHT_PROGBITS ||
+	    !(w(txthdr->sh_flags) & SHF_EXECINSTR) ||
 	    !is_mcounted_section_name(txtname))
 		return NULL;
 	return txtname;