boards/arm: Remove "LDFLAGS += -g" whichi is already added by Toolchain.defs

Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>

boards/arm/str71x/olimex-strp711/scripts/Make.defs

@@ -41,10 +41,6 @@ ifneq ($(CONFIG_WINDOWS_CYGWIN),y)
 endif
 endif
 
-ifeq ("${CONFIG_DEBUG_FEATURES}","y")
-  ARCHOPTIMIZATION = -g
-endif
-
 ifeq ($(OLDGCC),n)
   ARCHCPUFLAGS = -mcpu=arm7tdmi -mfloat-abi=soft
 else
@@ -67,7 +63,3 @@ NXFLATLDFLAGS2 = $(NXFLATLDFLAGS1) \
                  -T$(TOPDIR)/binfmt/libnxflat/gnu-nxflat-gotoff.ld \
                  -no-check-sections
 LDNXFLATFLAGS = -e main -s 2048
-
-ifeq ($(CONFIG_DEBUG_FEATURES),y)
-  LDFLAGS += -g
-endif