firefox: Use --disable-elf-hack option if supported
firefox: Use --disable-elf-hack option if supported

--disable-elf-hack option should specify with EXTRA_OECONF overrides.
Always specifying it causes confusion why disable-elf-hack is not effective
such as aarch64 and mips and so on.

Because Elf-hack supports arm, i586, and x86_64.
Other platforms is not supported and ignored such as aarch64(Arm 64bit).

ref: https://dxr.mozilla.org/mozilla-esr45/source/configure.in#7398

Signed-off-by: Hiroshi Hatake <a476a6e5b5893650242fbf0b2961500a9bd9032e@clear-code.com>

webdino/meta-browser,kraj/meta-browser,schnitzeltony/meta-browser,OSSystems/meta-browser,schnitzeltony/meta-browser,webdino/meta-browser,OSSystems/meta-browser,webdino/meta-browser,kraj/meta-browser,kraj/meta-browser,schnitzeltony/meta-browser,schnitzeltony/meta-browser,kraj/meta-browser,OSSystems/meta-browser,webdino/meta-browser,OSSystems/meta-browser,webdino/meta-browser