Fix typos in documentation (#1671)

Author: Aric5301

CMSIS/DoxyGen/RTOS2/src/cmsis_os2_Event.txt

@@ -30,7 +30,7 @@ Here is a simple example that shows how two thread can communicate with each oth
 \image html simple_signal.png "Simple event communication"
 
 The following steps are required to use event flags:
--# In the thread that is supposed to send a event with id sig1_id, call the set function:
+-# In the thread that is supposed to send an event with id sig1_id, call the set function:
 \code
 osDelay(1000U);                                           // wait for 1 second
 osEventFlagsSet(sig1_id, 0x0001U);                        // set the flag 0x0001U for event sig1_id

CMSIS/DoxyGen/RTOS2/src/cmsis_os2_Message.txt

@@ -7,7 +7,7 @@
 @details 
 \b Message \b passing is another basic communication model between threads. In the message passing model, one thread sends
 data explicitly, while another thread receives it. The operation is more like some kind of I/O rather than a direct access to
-information to be shared. In CMSIS-RTOS, this mechanism is called s \b message \b queue. The data is passed from one thread
+information to be shared. In CMSIS-RTOS, this mechanism is called a \b message \b queue. The data is passed from one thread
 to another in a FIFO-like operation. Using message queue functions, you can control, send, receive, or wait for messages. The
 data to be passed can be of integer or pointer type:
 
@@ -41,7 +41,7 @@ Specifies the following attributes for the \ref osMessageQueueNew function.
 /** 
 \fn osMessageQueueId_t osMessageQueueNew (uint32_t msg_count, uint32_t msg_size, const osMessageQueueAttr_t *attr)
 \details
-The function \ref osMessageQueueNew creates and initializes a  message queue object.
+The function \ref osMessageQueueNew creates and initializes a message queue object.
 The function returns a message queue object identifier or \token{NULL} in case of an error. 
 
 The function can be called after kernel initialization with \ref osKernelInitialize. It is possible to 

CMSIS/DoxyGen/RTOS2/src/cmsis_os2_ThreadFlags.txt

@@ -6,7 +6,7 @@
 \brief Synchronize threads using flags.
 \details
 Thread Flags are a more specialized version of the Event Flags. See \ref CMSIS_RTOS_EventFlags.
-While Event Flags can be used to globally signal a number of threads, thread flags are only send to a single specific thread.
+While Event Flags can be used to globally signal a number of threads, thread flags are only sent to a single specific thread.
 Every thread instance can receive thread flags without any additional allocation of a thread flags object.
 
 \note Thread flag management functions cannot be called from \ref CMSIS_RTOS_ISR_Calls "Interrupt Service Routines", except