Conditionally install jpm in meson.

meson.build

@@ -245,16 +245,18 @@ pkg.generate(libjanet,
 
 # Installation
 install_man('janet.1')
-install_man('jpm.1')
 install_headers(['src/include/janet.h', jconf], subdir: 'janet')
-patched_jpm = custom_target('patched-jpm',
-  input : ['tools/patch-jpm.janet', 'jpm'],
-  install : true,
-  install_dir : get_option('bindir'),
-  build_by_default : true,
-  output : ['jpm'],
-  command : [janet_nativeclient, '@INPUT@', '@OUTPUT@',
-    '--binpath=' + join_paths(get_option('prefix'), get_option('bindir')),
-    '--libpath=' + join_paths(get_option('prefix'), get_option('libdir'), 'janet'),
-    '--headerpath=' + join_paths(get_option('prefix'), get_option('includedir'))])
 install_data(sources : ['tools/.keep'], install_dir : join_paths(get_option('libdir'), 'janet'))
+if get_option('peg') and not get_option('reduced_os') and get_option('processes')
+  install_man('jpm.1')
+  patched_jpm = custom_target('patched-jpm',
+    input : ['tools/patch-jpm.janet', 'jpm'],
+    install : true,
+    install_dir : get_option('bindir'),
+    build_by_default : true,
+    output : ['jpm'],
+    command : [janet_nativeclient, '@INPUT@', '@OUTPUT@',
+      '--binpath=' + join_paths(get_option('prefix'), get_option('bindir')),
+      '--libpath=' + join_paths(get_option('prefix'), get_option('libdir'), 'janet'),
+      '--headerpath=' + join_paths(get_option('prefix'), get_option('includedir'))])
+endif