Blackbox 32K code cleanup

Cleaning up some missed 32K specific code.

src/main/blackbox/blackbox.c

@@ -1824,13 +1824,8 @@ void blackboxInit(void)
     // an I-frame is written every 32ms
     // blackboxUpdate() is run in synchronisation with the PID loop
     // targetPidLooptime is 1000 for 1kHz loop, 500 for 2kHz loop etc, targetPidLooptime is rounded for short looptimes
-    if (targetPidLooptime == 31) { // rounded from 31.25us
-        blackboxIInterval = 1024;
-    } else if (targetPidLooptime == 63) { // rounded from 62.5us
-        blackboxIInterval = 512;
-    } else {
-        blackboxIInterval = (uint16_t)(32 * 1000 / targetPidLooptime);
-    }
+    blackboxIInterval = (uint16_t)(32 * 1000 / targetPidLooptime);
+
     // by default p_ratio is 32 and a P-frame is written every 1ms
     // if p_ratio is zero then no P-frames are logged
     if (blackboxConfig()->p_ratio == 0) {

src/test/unit/blackbox_unittest.cc

@@ -103,20 +103,6 @@ TEST(BlackboxTest, TestInitIntervals)
     EXPECT_EQ(256, blackboxIInterval);
     EXPECT_EQ(8, blackboxPInterval);
     EXPECT_EQ(65536, blackboxSInterval);
-
-    // 16kHz PIDloop
-    targetPidLooptime = 63; // rounded from 62.5
-    blackboxInit();
-    EXPECT_EQ(512, blackboxIInterval); // note rounding
-    EXPECT_EQ(16, blackboxPInterval);
-    EXPECT_EQ(131072, blackboxSInterval);
-
-    // 32kHz PIDloop
-    targetPidLooptime = 31; // rounded from 31.25
-    blackboxInit();
-    EXPECT_EQ(1024, blackboxIInterval); // note rounding
-    EXPECT_EQ(32, blackboxPInterval);
-    EXPECT_EQ(262144, blackboxSInterval);
 }
 
 TEST(BlackboxTest, Test_500Hz)