Fix broken output text in Code Snippets

Signed-off-by: Adarsh <[email protected]>

backends/dpdk/README.md

@@ -68,7 +68,7 @@ To load the 'spec' file in dpdk follow the instructions in the
 - Currently, programs written for DPDK target should limit the functionality in Ingress blocks, in case non empty  Egress blocks are present it will be ignored by default unless Hidden temporary option `--enableEgress` used.  When egress block support gets added to the DPDK target, and compiler can generate separate spec file for non empty ingress and egress blocks then option `--enableEgress` will be removed.
 - DPDK architecture assumes the following signatures for programmable block of PSA. P4C-DPDK converts the input program to this form.
 
-```P4
+``` P4
 parser IngressParser (packet_in buffer, out H parsed_hdr, inout M user_meta);
 
 control Ingress (inout H hdr, inout M user_meta);

backends/p4tools/modules/testgen/README.md

@@ -114,7 +114,7 @@ P4Testgen supports the use of custom externs to restrict the breadth of possible
 
 #### Restricted Tests
 `testgen_assume(expr)` will add `expr` as a necessary path constraints to all subsequent execution. For example, for the following snippet
-```p4
+``` P4
 state parse_ethernet {
     packet.extract(headers.ethernet);
     testgen_assume(headers.ethernet.ether_type == 0x800);
@@ -130,7 +130,7 @@ only inputs which have `0x800` as Ethertype will be generated. This mode is enab
 #### Finding Assertion Violations
 Conversely, `testgen_assert(expr)` can be used to find violations in a particular P4 program. By default, `testgen_assert` behaves like `testgen_assume`. If the flag `--assertion-mode` is enabled, P4Testgen will only generate tests that will cause `expr` to be false and, hence, violate the assertion.
 For example, for
-```p4
+``` P4
 state parse_ethernet {
     packet.extract(headers.ethernet);
     transition select(headers.ethernet.ether_type) {

docs/CodingStandardPhilosophy.md

@@ -138,7 +138,7 @@ the `boost::format` for the format argument, which has some
 compatibility for `printf` arguments.  These functions handle IR and
 SourceInfo objects smartly.  Here is an example:
 
-```C++
+``` C++
 IR::NamedRef *ref;
 error(ErrorType::ERR_INVALID,
       "%1%: No header or metadata named '%2%'", ref->srcInfo, ref->name);

docs/IR.md

@@ -72,7 +72,7 @@ IR tree and accumulates information about the tree but does not modify
 it, while a Transform pass visits every node, possibly modifying the
 node or replacing it with some other node
 
-```C++
+``` C++
     /* pseudo-code for basic Transform visitor */
     visit(node, context=ROOT, visited={}) {
 	if (node in visited) {
@@ -152,7 +152,7 @@ As an example for how these are used in the IR visitor routines, the IR::If clas
 three children to visit -- a predicate and two consequents, with the value of the
 predicate deciding which consequent to execute.  The child visitor for `IR::If` is
 
-```C++
+``` C++
     visitor.visit(predicate);
     clone = visitor.flow_clone();
     visitor.visit(ifTrue);