gnu: icedtea-6: Fix build on aarch64-linux.

* gnu/packages/java.scm (icedtea-6)[source]: Add patch.
* gnu/packages/patches/icedtea-6-extend-hotspot-aarch64-support.patch:
New file.
* gnu/local.mk (dist_patch_DATA): Add it.

Signed-off-by: Efraim Flashner <efraim@flashner.co.il>

gnu/local.mk

@@ -1145,6 +1145,7 @@ dist_patch_DATA =						\
   %D%/packages/patches/icecat-use-older-reveal-hidden-html.patch	\
   %D%/packages/patches/icecat-use-system-graphite2+harfbuzz.patch	\
   %D%/packages/patches/icecat-use-system-media-libs.patch	\
+  %D%/packages/patches/icedtea-6-extend-hotspot-aarch64-support.patch	\
   %D%/packages/patches/icedtea-7-hotspot-gcc-segfault-workaround.patch  \
   %D%/packages/patches/icu4c-CVE-2020-10531.patch  		\
   %D%/packages/patches/id3lib-CVE-2007-4460.patch			\

gnu/packages/java.scm

@@ -827,6 +827,8 @@ machine.")))
               (sha256
                (base32
                 "0bg9sb4f7qbq77c0zf9m17p47ga0kf0r9622g9p12ysg26jd1ksg"))
+              (patches (search-patches
+                        "icedtea-6-extend-hotspot-aarch64-support.patch"))
               (modules '((guix build utils)))
               (snippet
                '(begin