add gcc-4.2.1_hpux_ia64 as a required platform

[SVN r48701]

status/explicit-failures-markup.xml

@@ -27,6 +27,7 @@
     <mark-toolset name="gcc-4.1.2_sunos_i86pc" status="required"/>
     <mark-toolset name="gcc-4.1.3_linux" status="required"/>
     <mark-toolset name="gcc-4.2.1" status="required"/>
+    <mark-toolset name="gcc-4.2.1_hpux_ia64" status="required"/>
     <mark-toolset name="gcc-4.2.1_linux_x86_64" status="required"/>
     <mark-toolset name="intel-linux-9.0" status="required"/>
     <mark-toolset name="intel-vc8-win-10.0" status="required"/>