lmdk: Add support for dynamic memory allocation by a loadable modules

This commit adds a necessary symbols in the linker script which allows use
a memory allocation functions from libc (malloc, calloc, etc.) in loadable
modules.

Signed-off-by: Adrian Warecki <adrian.warecki@intel.com>

lmdk/cmake/ldscripts/bss_linker_script.txt

@@ -16,5 +16,18 @@ SECTIONS {
         _next_end = ABSOLUTE(.);
         *(.bss)
         *(.bss.*)
+
+        /* Heap memory */
+        . = ALIGN(4);
+        __stack = .;
+        _end = .;
+        KEEP(*(.heap_mem))
+
+        /* Use the unused rest of the memory page as a heap */
+        . = ALIGN(4096);
+
+        /* The sbrk function implementation by xtensa incorrectly checks whether the allocated
+           memory block fits in the heap, so we have to add 1 to the end of the heap marker. */
+        _heap_sentry = . + 1;
     } >HPSRAM_seg : bss_phdr
 }

lmdk/cmake/ldscripts/data_linker_script.txt

@@ -11,6 +11,7 @@ SECTIONS {
         _data_start = ABSOLUTE(.);
         *(.data)
         *(.data.*)
+        *(.*.data)
         _data_end = ABSOLUTE(.);
     } >HPSRAM_seg : data_phdr