MAINTAINERS: Update no longer valid maintainers' status

The following maintainers' email addresses are no longer valid.

vipin.kumar@st.com
martin.krause@tq-systems.de
kim.phillips@freescale.com
fgretief@spaceteq.co.za

Update status of the components they used to maintain to be:
S: Orphaned (Since 2016-02)

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/MAINTAINERS b/MAINTAINERS
index b387207..9d447ea 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -126,8 +126,8 @@
 F:	arch/arm/include/asm/arch-s3c24x0/
 
 ARM STM SPEAR
-M:	Vipin Kumar <vipin.kumar@st.com>
-S:	Maintained
+#M:	Vipin Kumar <vipin.kumar@st.com>
+S:	Orphaned (Since 2016-02)
 T:	git git://git.denx.de/u-boot-stm.git
 F:	arch/arm/cpu/arm926ejs/spear/
 F:	arch/arm/include/asm/arch-spear/
@@ -309,8 +309,8 @@
 F:	arch/powerpc/cpu/mpc82*/
 
 POWERPC MPC83XX
-M:	Kim Phillips <kim.phillips@freescale.com>
-S:	Maintained
+#M:	Kim Phillips <kim.phillips@freescale.com>
+S:	Orphaned (Since 2016-02)
 T:	git git://git.denx.de/u-boot-mpc83xx.git
 F:	arch/powerpc/cpu/mpc83xx/
 F:	arch/powerpc/include/asm/arch-mpc83xx/
@@ -376,8 +376,8 @@
 F:	arch/sh/
 
 SPARC
-M:	Francois Retief <fgretief@spaceteq.co.za>
-S:	Maintained
+#M:	Francois Retief <fgretief@spaceteq.co.za>
+S:	Orphaned (Since 2016-02)
 T:	git git://git.denx.de/u-boot-sparc.git
 F:	arch/sparc/
 
@@ -390,8 +390,8 @@
 F:	include/spi*
 
 TQ GROUP
-M:	Martin Krause <martin.krause@tq-systems.de>
-S:	Maintained
+#M:	Martin Krause <martin.krause@tq-systems.de>
+S:	Orphaned (Since 2016-02)
 T:	git git://git.denx.de/u-boot-tq-group.git
 
 UBI