Update on descriptors

This PR improves the descriptors management.

• Fields computation is simplified and corrected in some corner cases
• Descriptor can now be given a name to improve debug/tracing information
• Tiles can also be individually named if CHAMELEON_KERNELS_TRACE cmake option is enabled
• core_ztile interface is updated to accept descriptor and print log calls (can be disable through environment variable CHAMELEON_COREBLAS_SILENT similarly to STARPU_SILENT)
• Recursive descriptors management is introduced as a first step toward recursive algorithm
• A CHAMELEON_Desc_Print function has been added to help debug the descriptor information (tile size, leading dimensions, ...)

Additionally:

• Fix a small issue with flush in starpu
• Silent warnings issued from the hmat merge
• Add the -Werror option to the CI build to avoid warnings
• Add a chameleon_ceil function to simplify computations in algorithms

runtime/openmp/control/runtime_options.c

@@ -25,15 +25,15 @@
 void RUNTIME_options_init( RUNTIME_option_t *option, CHAM_context_t *chamctxt,
                            RUNTIME_sequence_t *sequence, RUNTIME_request_t *request )
 {
-    option->sequence   = sequence;
-    option->request    = request;
-    option->profiling  = CHAMELEON_PROFILING == CHAMELEON_TRUE;
-    option->parallel   = CHAMELEON_PARALLEL == CHAMELEON_TRUE;
-    option->priority   = RUNTIME_PRIORITY_MIN;
-    option->ws_wsize   = 0;
-    option->ws_hsize   = 0;
-    option->ws_worker  = NULL;
-    option->ws_host    = NULL;
+    option->sequence  = sequence;
+    option->request   = request;
+    option->profiling = CHAMELEON_PROFILING == CHAMELEON_TRUE;
+    option->parallel  = CHAMELEON_PARALLEL == CHAMELEON_TRUE;
+    option->priority  = RUNTIME_PRIORITY_MIN;
+    option->ws_wsize  = 0;
+    option->ws_hsize  = 0;
+    option->ws_worker = NULL;
+    option->ws_host   = NULL;
     return;
 }