meta-phosphor: Add valgrind to obmc-phosphor-debugtools

Valgrind is useful for debugging memory corruption among other common
runtime misbehaviours.

Tested: `bitbake packagegroup-obmc-phosphor-debugtools -ne` and checked
the RDEPENDS structure for Witherspoon (ast2500 = no valgrind) and
Bletchley (ast2600 = with valgrind).

Change-Id: I1e9729b2feb5b535a0a240e68a0ee4f6b31b7490
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
diff --git a/meta-phosphor/recipes-phosphor/packagegroups/packagegroup-obmc-phosphor-debugtools.bb b/meta-phosphor/recipes-phosphor/packagegroups/packagegroup-obmc-phosphor-debugtools.bb
index edcc9ff..3118882 100644
--- a/meta-phosphor/recipes-phosphor/packagegroups/packagegroup-obmc-phosphor-debugtools.bb
+++ b/meta-phosphor/recipes-phosphor/packagegroups/packagegroup-obmc-phosphor-debugtools.bb
@@ -12,4 +12,10 @@
     lmsensors-sensors \
     tcpdump \
     screen \
+    valgrind \
     "
+
+# Some older arm architectures don't support valgrind, so explicitly remove
+# it as a dependency from them, but keep it by default in anything newer.
+RDEPENDS:${PN}:remove:armv5 = "valgrind"
+RDEPENDS:${PN}:remove:armv6 = "valgrind"