Merge pull request #3245 from haampie/fix/SED_ERE_OPT

drop -E flag in sed

lib/Makefile

@@ -298,7 +298,7 @@ INSTALL_DATA    ?= $(INSTALL) -m 644
 
 libzstd.pc: libzstd.pc.in
 	@echo creating pkgconfig
-	@sed $(SED_ERE_OPT) \
+	@sed \
 	        -e 's|@PREFIX@|$(PREFIX)|' \
 	        -e 's|@EXEC_PREFIX@|$(PCEXEC_PREFIX)|' \
 	        -e 's|@INCLUDEDIR@|$(PCINCPREFIX)$(PCINCDIR)|' \

lib/libzstd.mk

@@ -124,7 +124,6 @@ ifeq ($(HAVE_COLORNEVER), 1)
   GREP_OPTIONS += --color=never
 endif
 GREP = grep $(GREP_OPTIONS)
-SED_ERE_OPT ?= -E
 
 ZSTD_COMMON_FILES := $(sort $(wildcard $(LIBZSTD)/common/*.c))
 ZSTD_COMPRESS_FILES := $(sort $(wildcard $(LIBZSTD)/compress/*.c))