powerpc/head_check: use stdout for error messages

Prefer stderr instead of stdout for error messages.
This is a good practice and can help CI error detecting and
reporting (0day in this case).
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210815222334.9575-1-rdunlap@infradead.org

arch/powerpc/tools/head_check.sh

@@ -56,9 +56,9 @@ expected_start_head_addr=$vma
 start_head_addr=$(cat .tmp_symbols.txt | grep " t start_first_256B$" | cut -d' ' -f1)
 
 if [ "$start_head_addr" != "$expected_start_head_addr" ]; then
-	echo "ERROR: head code starts at $start_head_addr, should be $expected_start_head_addr"
-	echo "ERROR: try to enable LD_HEAD_STUB_CATCH config option"
-	echo "ERROR: see comments in arch/powerpc/tools/head_check.sh"
+	echo "ERROR: head code starts at $start_head_addr, should be $expected_start_head_addr" 1>&2
+	echo "ERROR: try to enable LD_HEAD_STUB_CATCH config option" 1>&2
+	echo "ERROR: see comments in arch/powerpc/tools/head_check.sh" 1>&2
 
 	exit 1
 fi
@@ -70,9 +70,9 @@ expected_start_text_addr=$(cat .tmp_symbols.txt | grep " a text_start$" | cut -d
 start_text_addr=$(cat .tmp_symbols.txt | grep " t start_text$" | cut -d' ' -f1)
 
 if [ "$start_text_addr" != "$expected_start_text_addr" ]; then
-	echo "ERROR: start_text address is $start_text_addr, should be $expected_start_text_addr"
-	echo "ERROR: try to enable LD_HEAD_STUB_CATCH config option"
-	echo "ERROR: see comments in arch/powerpc/tools/head_check.sh"
+	echo "ERROR: start_text address is $start_text_addr, should be $expected_start_text_addr" 1>&2
+	echo "ERROR: try to enable LD_HEAD_STUB_CATCH config option" 1>&2
+	echo "ERROR: see comments in arch/powerpc/tools/head_check.sh" 1>&2
 
 	exit 1
 fi