uboot: Cleaning up bootargs for prowl

 - Build bootarg contents in code, matching behaviour
of prowl/chimera
 - Add gfactive parameter to detect current partition

Matching change to ginstall: go/fibercl/79567
Removing hardcoded kernel cmdline: go/fibercl/79590

In reference to b/31805455, b/31805037

Change-Id: If9e3afd8499371ceb2d4ef69645fa2108b6933b8
diff --git a/board/ruby/ruby.c b/board/ruby/ruby.c
index 092f443..ebf499c 100644
--- a/board/ruby/ruby.c
+++ b/board/ruby/ruby.c
@@ -205,8 +205,9 @@
 #ifdef GFRG240
 	char cmd[320];
 	sprintf(cmd, "if test xx$HNV_ACTIVATED_KERNEL_NAME = xxkernel1; "
-	  "then gfkernel=0x%08x otherkernel=0x%08x; "
-	  "else gfkernel=0x%08x otherkernel=0x%08x; fi; "
+	  "then gfkernel=0x%08x otherkernel=0x%08x gfactive=kernel1; "
+	  "else gfkernel=0x%08x otherkernel=0x%08x gfactive=kernel0; fi; "
+	  "setenv bootargs gfactive=${gfactive} ${optargs} ${bootargs_extra}; "
 	  "gfloadaddr=0x%08x; kernelsize=0x%08x; ",
 	  UBOOT_PARTITION_OFFSET_KERNEL1, UBOOT_PARTITION_OFFSET_KERNEL0,
 	  UBOOT_PARTITION_OFFSET_KERNEL0, UBOOT_PARTITION_OFFSET_KERNEL1,