Remove hard-coded invocations of gcc; use cc(1) instead.

MFC after:	1 week

cddl/contrib/opensolaris/cmd/dtrace/test/tst/common/misc/tst.include.ksh

@@ -31,7 +31,6 @@ if [ $# != 1 ]; then
 fi
 
 dtrace=$1
-CC=/usr/bin/gcc
 CFLAGS=
 
 doit()
@@ -47,7 +46,7 @@ void
 main()
 {}
 EOF
-	if $CC $CFLAGS -o $cofile $cfile >/dev/null 2>&1; then
+	if cc $CFLAGS -o $cofile $cfile >/dev/null 2>&1; then
 		$dtrace -xerrtags -C -s /dev/stdin \
 		    >/dev/null 2>$errfile <<EOF
 #include <sys/$file>
@@ -67,11 +66,6 @@ EOF
 	rm -f $cofile $cfile 2>/dev/null
 }
 
-if [ ! -x $CC ]; then
-	echo "$0: bad compiler: $CC" >& 2
-	exit 1
-fi
-
 concurrency=`psrinfo | wc -l`
 let concurrency=concurrency*4
 let i=0

cddl/contrib/opensolaris/cmd/dtrace/test/tst/common/usdt/tst.noreap.ksh

@@ -51,7 +51,7 @@ provider test_prov {
 };
 EOF
 
-gcc -c test.c
+cc -c test.c
 if [ $? -ne 0 ]; then
 	print -u2 "failed to compile test.c"
 	exit 1
@@ -61,7 +61,7 @@ if [ $? -ne 0 ]; then
 	print -u2 "failed to create DOF"
 	exit 1
 fi
-gcc -o test test.o prov.o
+cc -o test test.o prov.o
 if [ $? -ne 0 ]; then
 	print -u2 "failed to link final executable"
 	exit 1

cddl/contrib/opensolaris/cmd/dtrace/test/tst/common/usdt/tst.noreapring.ksh

@@ -51,7 +51,7 @@ provider test_prov {
 };
 EOF
 
-gcc -c test.c
+cc -c test.c
 if [ $? -ne 0 ]; then
 	print -u2 "failed to compile test.c"
 	exit 1
@@ -61,7 +61,7 @@ if [ $? -ne 0 ]; then
 	print -u2 "failed to create DOF"
 	exit 1
 fi
-gcc -o test test.o prov.o
+cc -o test test.o prov.o
 if [ $? -ne 0 ]; then
 	print -u2 "failed to link final executable"
 	exit 1

cddl/contrib/opensolaris/cmd/dtrace/test/tst/common/usdt/tst.reap.ksh

@@ -51,7 +51,7 @@ provider test_prov {
 };
 EOF
 
-gcc -c test.c
+cc -c test.c
 if [ $? -ne 0 ]; then
 	print -u2 "failed to compile test.c"
 	exit 1
@@ -61,7 +61,7 @@ if [ $? -ne 0 ]; then
 	print -u2 "failed to create DOF"
 	exit 1
 fi
-gcc -o test test.o prov.o
+cc -o test test.o prov.o
 if [ $? -ne 0 ]; then
 	print -u2 "failed to link final executable"
 	exit 1