Phrase error messages as "Failed to", not "Could not" or "Couldn't" (#1298)

src/asm/main.cpp

@@ -259,7 +259,7 @@ int main(int argc, char *argv[])
 				dependFileName = musl_optarg;
 			}
 			if (dependfile == NULL)
-				err("Could not open dependfile %s", dependFileName);
+				err("Failed to open dependfile %s", dependFileName);
 			break;
 
 		case 'o':

src/asm/symbol.cpp

@@ -655,7 +655,7 @@ void sym_Init(time_t now)
 #endif
 
 	if (now == (time_t)-1) {
-		warn("Couldn't determine current time");
+		warn("Failed to determine current time");
 		// Fall back by pretending we are at the Epoch
 		now = 0;
 	}