utils: optimize split function

- Initialize start to 0 to avoid uninitialized variable warning.
- Use emplace_back instead of push_back to construct strings in
  place, improving performance and reducing unnecessary copies.

Change-Id: Ief54025f2114359e55bfc4312adc5220642f14a3
Signed-off-by: George Liu <liuxiwei@ieisystem.com>
diff --git a/common/utils.cpp b/common/utils.cpp
index 461cc08..80e1401 100644
--- a/common/utils.cpp
+++ b/common/utils.cpp
@@ -650,7 +650,7 @@
                                std::string_view trimStr)
 {
     std::vector<std::string> out;
-    size_t start;
+    size_t start = 0;
     size_t end = 0;
 
     while ((start = srcStr.find_first_not_of(delim, end)) != std::string::npos)
@@ -666,7 +666,7 @@
 
         if (!dstStr.empty())
         {
-            out.push_back(std::string(dstStr));
+            out.emplace_back(dstStr);
         }
     }