Blackfin arch: fix typo in register name

Signed-off-by: NMike Frysinger <michael.frysinger@analog.com>
Signed-off-by: NBryan Wu <bryan.wu@analog.com>

arch/blackfin/Kconfig

@@ -829,7 +829,7 @@ config L1_MAX_PIECE
 
 comment "Asynchonous Memory Configuration"
 
-menu "EBIU_AMBCTL Global Control"
+menu "EBIU_AMGCTL Global Control"
 config C_AMCKEN
 	bool "Enable CLKOUT"
 	default y