picolibc: Do not fail when "ninja test" fails

Ninja test fails when at least a single test fails. However,
non-0 return code prevents creating a stamp file.

Signed-off-by: Yuriy Kolerov <[email protected]>

Author: kolerov

Makefile.in

@@ -1164,7 +1164,7 @@ stamps/build-picolibc-perf-test: stamps/configure-picolibc-perf-test
 	mkdir -p $(dir $@) && touch $@
 
 stamps/check-libc-picolibc-perf: stamps/build-picolibc-perf-test $(SIM_STAMP)
-	ninja -C build-picolibc-perf-test test
+	ninja -C build-picolibc-perf-test test || true
 	date > $@
 
 stamps/configure-picolibc-nano-test: stamps/build-gcc-picolibc-stage2 $(PICOLIBC_SRCDIR) $(PICOLIBC_SRC_GIT)
@@ -1191,7 +1191,7 @@ stamps/build-picolibc-nano-test: stamps/configure-picolibc-nano-test
 	mkdir -p $(dir $@) && touch $@
 
 stamps/check-libc-picolibc-nano: stamps/build-picolibc-nano-test $(SIM_STAMP)
-	ninja -C build-picolibc-nano-test test
+	ninja -C build-picolibc-nano-test test || true
 	date > $@
 
 #