sysroot.proto: Clarification in doc block.

BUG=chromium:1124093
TEST=./generate.sh

Change-Id: I44fa38b402f5666851ac46796df7d666564215ef
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/infra/proto/+/2391118
Tested-by: Alex Klein <saklein@chromium.org>
Auto-Submit: Alex Klein <saklein@chromium.org>
Reviewed-by: Navil Perez <navil@google.com>
Commit-Queue: Navil Perez <navil@google.com>
diff --git a/go/chromite/api/sysroot.pb.go b/go/chromite/api/sysroot.pb.go
index f4014b3..ba2e6b9 100644
--- a/go/chromite/api/sysroot.pb.go
+++ b/go/chromite/api/sysroot.pb.go
@@ -565,8 +565,10 @@
 	Sysroot *Sysroot `protobuf:"bytes,1,opt,name=sysroot,proto3" json:"sysroot,omitempty"`
 	// The install packages flags.
 	Flags *InstallPackagesRequest_Flags `protobuf:"bytes,2,opt,name=flags,proto3" json:"flags,omitempty"`
-	// A list of specific packages to install. Will generate the list of packages
-	// for the build target if none are specified.
+	// Optional.
+	// A list of specific package atoms to install. Will generate
+	// the list of packages for the build target if none are
+	// specified. The version of the packages is ignored if provided.
 	Packages []*chromiumos.PackageInfo `protobuf:"bytes,3,rep,name=packages,proto3" json:"packages,omitempty"`
 	// The chroot to use to execute the endpoint.
 	Chroot *chromiumos.Chroot `protobuf:"bytes,4,opt,name=chroot,proto3" json:"chroot,omitempty"`
diff --git a/src/chromite/api/sysroot.proto b/src/chromite/api/sysroot.proto
index f19c224..24fbc4a 100644
--- a/src/chromite/api/sysroot.proto
+++ b/src/chromite/api/sysroot.proto
@@ -117,8 +117,10 @@
   Sysroot sysroot = 1;
   // The install packages flags.
   Flags flags = 2;
-  // A list of specific packages to install. Will generate the list of packages
-  // for the build target if none are specified.
+  // Optional.
+  // A list of specific package atoms to install. Will generate
+  // the list of packages for the build target if none are
+  // specified. The version of the packages is ignored if provided.
   repeated chromiumos.PackageInfo packages = 3;
   // The chroot to use to execute the endpoint.
   chromiumos.Chroot chroot = 4;