8183262: noexecstack check in os::dll_load on Linux is too expensive
Summary: convert ElfFile::specifies_noexecstack() to static method which read file header and check executable stack flag.
Reviewed-by: iklam, stuefe
^build/
^dist/
^.idea/
nbproject/private/
^webrev
^.src-rev$
^.jib/
.DS_Store
.metadata/
.recommenders/