boot: cover for hardware keys on phones/tablets

The patch is originally from Brenton Simpson, I (Lennart) just added some
comments and rebased it.

I didn't test this, but the patch looks so obviously right to me, that
I think we should just merge it, instead of delaying this further. In
the worst case noone notices, in the best case this makes sd-boot work
reasonably nicely on devices that only have a hadware power key + volume
rocker.

Fixes: #30598
Replaces: #31135
(cherry picked from commit 2fda6f5)
(cherry picked from commit 71de25f)
(cherry picked from commit 80c7571)

Author: appsforartists

src/boot/efi/boot.c

@@ -826,13 +826,15 @@ static bool menu_run(
 
                 switch (key) {
                 case KEYPRESS(0, SCAN_UP, 0):
+                case KEYPRESS(0, SCAN_VOLUME_UP, 0):  /* Handle phones/tablets that only have a volume up/down rocker + power key (and otherwise just touchscreen input) */
                 case KEYPRESS(0, 0, 'k'):
                 case KEYPRESS(0, 0, 'K'):
                         if (idx_highlight > 0)
                                 idx_highlight--;
                         break;
 
                 case KEYPRESS(0, SCAN_DOWN, 0):
+                case KEYPRESS(0, SCAN_VOLUME_DOWN, 0):
                 case KEYPRESS(0, 0, 'j'):
                 case KEYPRESS(0, 0, 'J'):
                         if (idx_highlight < config->n_entries-1)
@@ -870,9 +872,10 @@ static bool menu_run(
 
                 case KEYPRESS(0, 0, '\n'):
                 case KEYPRESS(0, 0, '\r'):
-                case KEYPRESS(0, SCAN_F3, 0): /* EZpad Mini 4s firmware sends malformed events */
-                case KEYPRESS(0, SCAN_F3, '\r'): /* Teclast X98+ II firmware sends malformed events */
+                case KEYPRESS(0, SCAN_F3, 0):      /* EZpad Mini 4s firmware sends malformed events */
+                case KEYPRESS(0, SCAN_F3, '\r'):   /* Teclast X98+ II firmware sends malformed events */
                 case KEYPRESS(0, SCAN_RIGHT, 0):
+                case KEYPRESS(0, SCAN_SUSPEND, 0): /* Handle phones/tablets with only a power key + volume up/down rocker (and otherwise just touchscreen input) */
                         exit = true;
                         break;