Make egrep only set REG_EXTENDED flag.

findutils/grep.c

@@ -245,7 +245,6 @@ extern int grep_main(int argc, char **argv)
 
 #ifdef CONFIG_FEATURE_GREP_EGREP_ALIAS
 	if (strcmp (basename (argv[0]), "egrep") == 0)
-		reflags |= REG_ICASE;
 		reflags |= REG_EXTENDED;
 #endif
 

testsuite/grep/egrep-is-not-case-insensitive

@@ -0,0 +1 @@
+test x`echo foo | busybox egrep FOO` = x

testsuite/grep/egrep-supports-extended-regexps

@@ -0,0 +1 @@
+test x`echo foo | busybox egrep fo+` = xfoo