hush: complete renaming CONFIG_SYS_HUSH_PARSER to CONFIG_HUSH_PARSER

There is no more define of CONFIG_SYS_HUSH_PARSER.  Rename some
remaining references and drop the backward compatible Kconfig entry.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
diff --git a/cmd/Makefile b/cmd/Makefile
index 9ce7861..a1731be 100644
--- a/cmd/Makefile
+++ b/cmd/Makefile
@@ -49,7 +49,7 @@
 obj-$(CONFIG_CMD_EEPROM) += eeprom.o
 obj-$(CONFIG_EFI_STUB) += efi.o
 obj-$(CONFIG_CMD_ELF) += elf.o
-obj-$(CONFIG_SYS_HUSH_PARSER) += exit.o
+obj-$(CONFIG_HUSH_PARSER) += exit.o
 obj-$(CONFIG_CMD_EXT4) += ext4.o
 obj-$(CONFIG_CMD_EXT2) += ext2.o
 obj-$(CONFIG_CMD_FAT) += fat.o
@@ -123,7 +123,7 @@
 obj-$(CONFIG_CMD_TERMINAL) += terminal.o
 obj-$(CONFIG_CMD_TIME) += time.o
 obj-$(CONFIG_CMD_TRACE) += trace.o
-obj-$(CONFIG_SYS_HUSH_PARSER) += test.o
+obj-$(CONFIG_HUSH_PARSER) += test.o
 obj-$(CONFIG_CMD_TPM) += tpm.o
 obj-$(CONFIG_CMD_TPM_TEST) += tpm_test.o
 obj-$(CONFIG_CMD_TSI148) += tsi148.o