GCC12: Convert array comparisons to pointer-to-first-element comparis…

…ons.

These are equivalent, but the former is deprecated in C++20 and warned by GCC12.

[The above message is from an earlier equivalent commit in FlashFloppy.
It is also equivalent to part of PR #5 created by kimstik@github]

src/blinky.c

@@ -213,7 +213,7 @@ int main(void)
     unsigned int nr_tim = 4;
 
     /* Relocate DATA. Initialise BSS. */
-    if (_sdat != _ldat)
+    if (&_sdat[0] != &_ldat[0])
         memcpy(_sdat, _ldat, _edat-_sdat);
     memset(_sbss, 0, _ebss-_sbss);
 

src/fw_update.c

@@ -304,7 +304,7 @@ static bool_t enter_bootloader(void)
 int main(void)
 {
     /* Relocate DATA. Initialise BSS. */
-    if (_sdat != _ldat)
+    if (&_sdat[0] != &_ldat[0])
         memcpy(_sdat, _ldat, _edat-_sdat);
     memset(_sbss, 0, _ebss-_sbss);
 

src/main.c

@@ -25,7 +25,7 @@ static void canary_check(void)
 int main(void)
 {
     /* Relocate DATA. Initialise BSS. */
-    if (_sdat != _ldat)
+    if (&_sdat[0] != &_ldat[0])
         memcpy(_sdat, _ldat, _edat-_sdat);
     memset(_sbss, 0, _ebss-_sbss);