specs/arm: Remove specs that are not used

Most of these configurations never have produced a stage that has gone
on the mirrors. For simplity of maintenance, remove them until we find a
reason to add them to our autobuilds.

Signed-off-by: Matt Turner <mattst88@gentoo.org>

releases/specs/arm/armv7a/stage1.spec

@@ -1,8 +0,0 @@
-subarch: armv7a
-version_stamp: @TIMESTAMP@
-target: stage1
-rel_type: default
-profile: default/linux/arm/17.0/armv7a
-snapshot: @TIMESTAMP@
-source_subpath: default/stage3-armv7a-latest
-update_seed: yes

releases/specs/arm/armv7a/stage2.spec

@@ -1,7 +0,0 @@
-subarch: armv7a
-version_stamp: @TIMESTAMP@
-target: stage2
-rel_type: default
-profile: default/linux/arm/17.0/armv7a
-snapshot: @TIMESTAMP@
-source_subpath: default/stage1-armv7a-@TIMESTAMP@

releases/specs/arm/armv7a/stage3.spec

@@ -1,7 +0,0 @@
-subarch: armv7a
-version_stamp: @TIMESTAMP@
-target: stage3
-rel_type: default
-profile: default/linux/arm/17.0/armv7a
-snapshot: @TIMESTAMP@
-source_subpath: default/stage2-armv7a-@TIMESTAMP@