Do not generate manpages for the tools if we do not have help2man.

configure.ac

@@ -1521,6 +1521,9 @@ if test "x$ICC" != "x"; then
 fi
 AM_CONDITIONAL([STARPU_HAVE_ICC], [test "x$ICC" != "x"])
 
+# Do not generate manpages for the tools if we do not have help2man
+AC_CHECK_PROGS([HELP2MAN], [help2man])
+AM_CONDITIONAL([STARPU_HAVE_HELP2MAN], [test "x$HELP2MAN" != "x"])
 AC_CHECK_MEMBER([struct cudaDeviceProp.pciDomainID],
   AC_DEFINE([STARPU_HAVE_DOMAINID],[1],[Define to 1 if CUDA device properties include DomainID]),
   , [[#include <cuda_runtime_api.h>]])

tools/Makefile.am

@@ -50,6 +50,7 @@ dist_bin_SCRIPTS +=	\
 	starpu_top
 
 
+if STARPU_HAVE_HELP2MAN
 starpu_calibrate_bus.1: starpu_calibrate_bus
 	help2man --no-discard-stderr -N ./starpu_calibrate_bus > starpu_calibrate_bus.1
 
@@ -62,9 +63,9 @@ starpu_perfmodel_display.1: starpu_perfmodel_display
 starpu_perfmodel_plot.1: starpu_perfmodel_plot
 	help2man --no-discard-stderr -N ./starpu_perfmodel_plot > starpu_perfmodel_plot.1
 
-
 dist_man1_MANS =\
 	starpu_calibrate_bus.1 \
 	starpu_machine_display.1 \
 	starpu_perfmodel_display.1 \
 	starpu_perfmodel_plot.1
+endif