Fix some errors found during upstream merge

Documentation/acronyms.txt

@@ -52,6 +52,7 @@ LAN    Local Area Network (networking)
 LCD    Liquid Crystal Display
 LIBC   The "C" Library
 LIBM   The "C" Math Library
+LP     Low Power
 MAC    Media Access Control (networking, OSI model)
 MCI    Memory Card Interface
 MCU    Microcontroller Unit
@@ -77,6 +78,7 @@ PROM   Programmable Read-Only Memory
 OS     Operating System
 OTG    On-The-Go (USB)
 OTP    One-Time Programmable
+POR    Power-On Reset
 PWM    Pulse Width Modulation
 PKT    "Raw" Packet socket (networking)
 PRNG   Pseudo-Random Number Generator
@@ -115,4 +117,5 @@ WAN    Wide Area Network (networking)
 WLAN   Wireless Local Area Network (networking)
 WPAN   Wireless Personal Area Network (networking)
 WDT    Watchdog Timer (hardware)
+XIP    eExecute In Place
 XDMAC  Extended DMA Controller (Atmel)

arch/arm/src/stm32/stm32l15xxx_rtcc.c

@@ -94,7 +94,7 @@
 #endif
 
 #if !defined(CONFIG_STM32_RTC_MAGIC_TIME_SET)
-#  define CONFIG_STM32_RTC_MAGIC_TIME_SET (0xfoodface)
+#  define CONFIG_STM32_RTC_MAGIC_TIME_SET (0xf00dface)
 #endif
 
 #if !defined(CONFIG_STM32_RTC_MAGIC_REG)

arch/arm/src/stm32l4/Kconfig

@@ -1426,7 +1426,7 @@ config STM32L4_HAVE_RTC_SUBSECONDS
 	select ARCH_HAVE_RTC_SUBSECONDS
 	default y
 
-config STM32F4_RTC_MAGIC_REG
+config STM32L4_RTC_MAGIC_REG
 	int "BKP register"
 	default 0
 	range  0 31
@@ -1434,13 +1434,13 @@ config STM32F4_RTC_MAGIC_REG
 		The BKP register used to store/check the Magic value to determine if
 		RTC is already setup
 
-config STM32F4_RTC_MAGIC
+config STM32L4_RTC_MAGIC
 	hex "RTC Magic 1"
 	default 0xfacefeed
 	---help---
 		Value used as Magic to determine if the RTC is already setup
 
-config STM32F4_RTC_MAGIC_TIME_SET
+config STM32L4_RTC_MAGIC_TIME_SET
 	hex "RTC Magic 2"
 	default 0xf00dface
 	---help---

mm/iob/iob_navail.c

@@ -61,11 +61,15 @@ int iob_navail(void)
   int navail = 0;
   int ret;
 
+#if CONFIG_IOB_NCHAINS > 0
   ret = nxsem_getvalue(&g_qentry_sem, &navail);
   if (ret >= 0)
     {
       ret = navail;
     }
+#else
+  ret = navail;
+#endif
 
   return ret;
 }